Applications Of Analog Switches Biology Essay

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Abstract: This tutorial outlines the basic construction, operation, and applications of analog switches. On-resistance, flatness, charge-injection, and leakage, each a performance-related specification, are defined. Features including ESD-protection, fault-protection, and force-sense capability are explained. Application-specific video, USB, HDMI, PCIe switches are outlined as well.

Also see application note 4653, "FAQs about analog switches."

Introduction:

First developed about 25 years ago, integrated analog switches often form the interface between analog signals and a digital controller. This article provides an overview of the general-purpose and application specific analog switches. The first section presents the theoretical basis for analog switches and describes common parameters such as on-resistance, RON flatness, leakage, charge-injection, and off-isolation.

In recent years, integrated analog switches have offered better switching characteristics, lower supply voltages, smaller packages, and integrated ESD protection. Specific application of analog switches feature T-switches, Crosspoint switches, calibration multiplexers (cal-MUXes), fault-protected switches, and force-sense switches. This application note discusses as well high-speed USB, HDMI, and PCIe switches.

Because so many performance options and special functions are available, the well-informed product designer can usually find the right part for a particular application.

Standard analog Switch:

CMOS analog switches are easy to use, so most designers take them for granted. But one should not forget that these switches solve specific engineering problems. Conventional analog switches like the early (2 SPDT) DG403 or the MAX383 are now offered by many semiconductor manufacturers; their structure is shown in Figure 1a. Maxim also offers devices such as the MAX14504, which offers better performance and smaller package size. The MAX14504 reduces board space over the older 2 SPDT configured devices (MAX383).

(a) (b)

Figure 1. The internal construction of a typical analog switch features parallel n- and p-channel MOSFETs (b) and the gate-drive circuitry. (b).

Basic analog switch principles are connecting an n-channel MOSFET in parallel with a p-channel MOSFET that allows signals to pass in either direction with equal ease. Whether the n- or the p-channel device carries more signal current depends on the ratio of input to output voltage. Because the switch has no preferred direction for current flow, it has no preferred input or output. The two MOSFETs are switched on and off by internal inverting and non-inverting amplifiers.

These amplifiers level-shift the digital input signal as required, according to whether the signal is CMOS- or TTL-logic-compatible and whether the analog supply voltage is single or dual. In CMOS-logic the control circuitry consists of far more components as logic "NOT" section. It consists of a reference voltage stage, comparator and an inverting buffer (Figure 1b) as described in "Analogschalter in der Praxis Teil 1".

In some low capacitance applications only n-channel MOSFETs with charge pump are used (the MAX4887, for example) as p-channel MOSFETs increase the parasitic capacitance of a switch. Charge pump switches allow input signal to exceed above/below the supply voltage. The MAX14504, for instance integrates a charge pump to support high output-signal range (±VCC) with negative signal capability while eliminating the need for a negative supply. However, charge pump switches require additional power for additional circuitry.

Low-resistance switches:

Taking the p- and n-channel on-resistances (RON) in parallel (product over sum) for each level of VIN yields a composite on-resistance characteristic for the parallel structure (Figure 2). This plot of RON versus VIN can be described as linear if you exclude the effects of temperature, power-supply voltage, and RON variation with analog input voltage. RON should be as low as possible in order to keep signal loss and Propagation delay small, a RC time constant function of on-resistance and load capacitance. By reducing RON the Width/Length (W/L) ratio of a MOSFET must be increased, resulting in higher parasitic capacitance and larger silicon area; larger parasitic capacitance reduces the bandwidth. W and L are not the only parameters for RON, it is complex function of electron and hole mobility (µn and µp), oxide capacitance COX, threshold voltage VT, and VGS (signal voltage VIN) of N- and P-MOSFETs shown in Equation 1a/b. You should be aware that these effects represent disadvantages and that minimizing them is often the primary purpose of new products. See Table 1.

Figure 2. The n-channel and p-channel on-resistances of Figure 1 form a low-valued composite on-resistance.

(Eq.1a)

(Eq.1b)

Table 1. Low-resistance switches

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Match(Ω,max)

RON Flatness (Ω,max)

tON/tOFF(ns,max)

Charge Injection (pC,max)

Supply Voltage Range (V)

Pin-Package

MAX14535E

1 DPDT; NO

0.35

10

0.05

0.001

90000/40000

-

+2.4 to +5.5

10-UTQFN

MAX4715/MAX4716

1 SPST; NO/NC

0.4

1

-

0.09

18/12

20

+1.6 to +3.6

5-SC70

MAX4735

4 SPDT

0.4

100

0.03

0.75

200/180

100

+1.6 to +3.6

16-TQFN/TSSOP

MAX14504

2 SPDT; Bi-Directonal

0.5

50

-

0.001

60000/3000

-

+2.3 to +5.5

12-WLP

MAX4626

1 SPST; NO

0.5

2

-

0.1

50/30

40

+1.8 to +5.5

5-SOT

MAX4742

2 DPST; NC

0.8

1

0.08

0.18

24/16

28

+1.6 to +3.6

8-µDFN/µMAX/SOT

MAX4754

4 DPDT

0.85

3

0.35

0.4

140/50

50

+1.8 to +5.5

16-TQFN/UCSP

MAX4758/MAX4759

4 DPDT/8 SPDT

0.85

5

0.35

0.45

140/50

40

+1.8 to +5.5

36-TQFN; 32-UCSP/WLP

MAX4751/MAX4752

4 SPST; NO/NC

0.9

2.5

0.12

0.1

30/25

21

+1.6 to +3.6

16-QFN/14-TSSOP

MAX4855

2 SPDT

1

2

0.12

0.275

60/40

8

+2 to +5.5

16-TQFN

MAX4783

3 SPDT

1

2

0.4

0.2

25/15

40

+1.6 to +3.6

16-QFN/TQFN/TSSOP

MAX4680/MAX4690/MAX4700

2 SPST; NC/NO/NO-NC

1.25

0.5

0.3

0.3

275/175

550

±4.5 to ±20

16-PDIP(N)/SOIC(W)/SSOP

MAX4677/MAX4678/MAX4679

4 SPST; NC/NO/NO-NC

1.6

1

0.3

0.4

350/150

85

±2.7 to ±5.5

16-PDIP(N)/TSSOP

MAX4688

1 SPDT

2.5

0.5

0.4

1

30/12

40

+1.8 to +5.5

6-UCSP

MAX4661/MAX4662/MAX4663

4 SPST; NC/NO/NO-NC

2.5

0.5

0.5

0.5

275/175

300

±4.5 to ±20

16-PDIP(N)/SOIC(W)/SSOP

MAX4667

2 SPST; NC

2.5

0.5

0.4

0.4

275/175

450

±4.5 to ±20

16-PDIP(N)/SOIC(N)

MAX4706/MAX4707

1 SPST; NC/NO

3

1

-

0.85

20/15

5

+1.8 to +5.5

6-µDFN/SC70; 5-SC70

MAX4675/MAX4676

1 SPST; NO/NC

3

1

-

0.7

300/110

87

±2.7 to ±5.5

6-SOT

MAX4674

4 SPDT

4

0.5

0.4

0.8

18/66

10

+1.8 to +5.5

16-QSOP/SOIC(N)/TQFN/TSSOP

MAX4664/MAX4665/MAX4666

4 SPST; NC//NO/NO-NC

4

0.5

0.5

0.5

275/175

300

±4.5 to ±20

16-PDIP(N)/SOIC(N)

MAX4739

4 SPST; NO-NC

4.5

0.5

0.4

1.2

80/40

5

+1.8 to +5.5

14-TSSOP/UCSP

MAX4621/MAX4622/MAX4623

2 SPST/2 SPDT/2 DPST; NO/-/NO

5

0.5

0.5

0.5

250/200

480

±4.5 to ±20

16-PDIP(N)/SOIC(N)

MAX4947/MAX4948

6 SPDT; -/Bi-Directional

5.5

3

0.5

1

800/800

10

+1.8 to +5.5

24-TQFN/25-UCSP

MAX4729/MAX4730

1 SPDT

5.5

2

0.15/0.34

1.5/0.95

45/26

3

+1.8 to +5.5

6-µDFN/SC70

MAX4670

8 SPDT; NO-NC

9

0.01

0.15

0.18

400/200

8

+2.7 to +3.6

32-TQFN

MAX14756/MAX14757/MAX14758

4 SPST; NC/NO/NO-NC

10

2.5

0.5

0.004

60000/3000

580

±10 to ±35

16-TSSOP

The first analog switches operated on ±20V supply voltages and had several hundred ohms of RON. Recent products (the MAX4992, for example) achieve 0.5Ω maximum RON with a much lower supply voltage. Supply voltage and applied signal have a substantial effect on RON (Figure 3a). The MAX4992 specifies signal and supply voltages from 1.8V to 5.5V. As you can see, RON increases for lower supply voltages. The max RON is about 0.38Ω at 1.8V, 0.3Ω at 2.7V, 0.28Ω at 3.3V and only 0.25Ω at 5V. Many new analog switches (the MAX4735, for example) specify low-voltage operation for supply voltages down to 1.6V. The MAX4992 achieves very low on-resistance and RON flatness (1m Ω) with a single-supply. For 5V supplies, Figure 3b compares the Maxim switches with older types. Depending on the application Maxim offer many analog switches that operate with single- or/and dual-supplies.

Figure 3a. Higher supply voltage causes lower on-resistance.

Figure 3b. At +5V supply voltage, later-generation analog switches have lower on-resistance.

When selecting switches for single-supply systems, try to choose from those intended for single-supply use. Such devices save one pin, because they do not require separate V- and ground pins. As a result, this economy of pins enables a single-pole/double-throw (SPDT) switch to fit into a miniscule 6-pin SOT23 package. Similarly, low-voltage dual-supply applications call for dual-supply switches. These switches require a V- pin in addition to the ground pin, and typically specify a logic interface with standard CMOS and TTL levels. The SPST MAX4529, for example, is also available in a 6-pin SOT23 package.

Many high-performance analog systems still rely on higher-level bipolar supplies such as ±15V or ±12V. The interface to these voltages requires an additional supply pin commonly known as logic supply voltage (shown in the MAX14756 data sheet). This pin (VL) connects to the system logic voltage, which is usually 5V or 3.3V. Having the input logic signals referenced to the actual logic levels increases the noise margin and prevents excessive power dissipation.

Often misunderstood is the analog-switch concept pertaining to input logic levels and their effect on supply current. If the logic inputs are at ground or VCC (or VL when available), analog switches have essentially no supply current. Applying TTL levels to a 5V switch, however, can cause the supply current to increase more than 1000 times. To avoid unnecessary power consumption, you should avoid TTL levels, which are simply a legacy of the 1980s.

Signal Handling

Figure 3a also shows the value of RON versus signal voltage. These curves fall within the specified range of supply voltage, because analog switches can only handle analog-signal levels between the supply voltages. Under- or overvoltage inputs can permanently damage a protected switch by producing uncontrolled currents through internal diode networks. Normally, these diodes protect the switch against short-duration electrostatic discharge (ESD) as high as ±2kV.

RON for a typical CMOS analog switch causes a linear reduction of signal voltage that is proportional to current passing through the switch. This might not be a disadvantage for modest levels of current or if the design accounts for RON effects. However, if you accept a certain level of RON, then channel matching and RON flatness can interest you. Channel matching describes the variation of RON for the channels of one device; RON flatness describes the variation of RON versus signal range for a single channel. Typical values for these parameters are below 0.1Ω to 5Ω, for very low RON switches smaller values of channel matching and RON flatness can be achieved. These parameters for the MAX4992 are 3mΩ and 1mΩ, respectively. The MAX14535E for example achieves typically 0.135Ω RON and 0.3mΩ RON flatness. This product is ideal for portable devices in AC-coupled audio or video, handling negative-rails down to -1.5V. The smaller the ratio of matching/RON or flatness/RON is, the more accurate the switch.

In most applications, you can avoid excessive switch current by modifying the circuit design. To change the gain of an op amp by switching between different feedback resistances, for example, choose a configuration that places the switch in series with a high-impedance input (Figure 4a). Because switch currents are insignificant, you can ignore the value of RON and its temperature coefficient. Switch current in the alternative design (Figure 4b) can be substantial, because it depends on the output voltage.

Figure 4a b. Gain-control circuits are good (a) or bad (b) depending on the amount of current through the switch.

A major performance requirement in all audio systems is elimination of audible clicks and pops. It does not matter how good the audio performance of a device is. If it makes a noisy click every time the system turns on, the perceived quality of the product is instantly degraded. Fortunately, there are solutions to remove nearly every source of click and pop problems. Join us for a discussion about the definition of click and pop, what causes it, and how to eliminate it.

Break-Before-Make

Turn-on and turn-off times (tON and tOFF) for most analog switches vary from below 15ns to as high as 1µs. For Maxim's "clickless" audio switches (Table 2), tON and tOFF are in the millisecond range to eliminate the audible clicks otherwise present when switching audio signals. The MAX4992, for example features a slow turn-on time limiting clip-and-pop noise without extra components. Common sources of audible clicks and pops are due to powering up/down audio sources and output-coupling capacitor. Another technique suppressing clicks and pops is by using internal shunt switches. The MAX4744, for instance has internal shunt switches that discharges any unconnected output terminals to ground. Additional Break-Before-Make feature ensures breaking a connection first before a new connection is engaged. Maxim's clickless switches use the combination of shunt switches and Break-Before-Make feature to avoid a step DC voltage switched into the speaker thus reducing clicks and pops.

The relative magnitudes are also important: tON > tOFF yields break-before-make action, and tOFF > tON yields make-before-break. This distinction is critical for some applications as mention earlier. Figure 5a shows that you must take care in switching between the two gains. One switch is normally closed in a typical make-before-break application. In changing gain you must avoid opening both switches at once; that is, the second switch must close before the first switch opens. Otherwise, the op amp applies open-loop gain and drives its output to the rails. The opposite configuration (break-before-make) is also useful in switching among different input signals to a single op amp. To avoid short circuits between the input channels, a given connection must be switched off before the next one is switched on.

Table 2. Clickless analog switches

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Match(Ω,max)

RON Flatness (Ω,max)

tON/tOFF(ns,max)

Charge Injection (pC,max)

Supply Voltage Range (V)

Pin-Package

MAX4992

2 SPDT; Bi-Directional

0.5

100

0.003

0.001

150000/2000

-

+1.8 to +5.5

10-UTQFN

MAX4744/MAX4746H

2 SPDT

0.95

15

0.1

0.55

560/540

450

+1.8 to +5.5

10-µDFN

MAX4910

4 SPDT

0.8

-

0.1

0.35

150/1000

300

+1.8 to +5.5

16-TQFN

MAX4764/MAX4765

2 SPDT

0.85

2

0.1

0.4

80/70

150

+1.8 to +5.5

10-TDFN-EP/UCSP

MAX4908/ MAX4930

2 SP3T

0.8

50

0.1

0.35

-

-

+1.8 to +5.5

14-TDFN-EP

MAX4901/MAX4902

2 SPST; NO

1

6

0.25

0.5

100/100

125

+1.8 to +5.5

8-TDFN-EP; 9-UCSP

MAX4571/MAX4573

11 SPST; NO

35

0.2

3

6

8000/300

 

+2.7 to +5.25

28-QSOP/SOIC(W)/SSOP

MAX4572/MAX4574

2 SPST + 2 SPDT

35

0.2

3

6

8000/300

 

+2.7 to +5.25

28-QSOP/SOIC(W)/SSOP

MAX4562/MAX4563

2 SPST + 2 SPDT

20

1

5

5

12000/-

 

+2.7 to +5.5

16-QSOP

When a changing signal level modulates the on-resistance, causing a variation in the insertion loss, analog switches generate total harmonic distortion (THD). Consider a 100Ω switch with 10Ω RON flatness, for example. Loading this switch with a 600Ω termination produces 0.24% of THD. THD can be critical in some application determining the quality or fidelity of a signal passing through a switch. Audio applications that require low RON flatness and THD specification, appropriate components selection and board layout design are vital task. THD is defined as a ratio of a square root of all squared harmonic components divided by its fundamental harmonic component shown in Equation 2a. The maximum THD is calculated as shown in Equation 2b. The MAX4992, for instance has a very low THD (0.004%). Figure 5 shows some THD comparison for different switches.

(Eq.2a)

(Eq.2b)

FIGURE 5 MISSING

Charge-Injection Effects

As mentioned above, low RON is not necessary in all applications. Lower RON requires greater chip area. The result is a greater input capacitance whose charge and discharge currents dissipate more power in every switching cycle. Based on the time constant t = RC, this charging time depends on load resistance (R) and capacitance (C). It normally lasts a few tens of nanoseconds, but low-RON switches have longer-duration on and off periods. High-RON switches are faster.

Maxim offers both types of switches, each with the same pinout in the same miniature SOT23 package. The MAX4501 and the MAX4502 specify higher on-resistance but shorter on/off times. The MAX4514 and the MAX4515 have lower on-resistance but longer switching times. Another negative consequence of low on-resistance can be the higher charge injection caused by higher levels of capacitive gate current. A certain amount of charge is added to or subtracted from the analog channel with every on or off transition of the switch (Figure 6a). For switches connected to high-impedance outputs, this action can cause significant changes in the expected output signal. A small parasitic capacitor (CL) with no other load adds a variation of ΔVOUT, so charge injection can be calculated as Q = ΔVOUTCL.

A track/hold amplifier, which maintains a constant analog output during conversion by an A/D converter, offers a good example of this (Figure 6b). Closing S1 charges the small buffer capacitor (C) to the input voltage (VS). The value of C is only a few picofarads, and VS remains stored on C when S1 opens. The held voltage (VH) is applied to the buffer by closing S2 at the beginning of a conversion. The high-impedance buffer then maintains VH constant over the ADC's conversion time. For short acquisition times, the track/hold's capacitor must be small and S1's on-resistance must be low. On the other hand, charge injection can cause VH to change by ±ΔVOUT (a few millivolts), thereby affecting the accuracy of the following ADC.

Figure 6a. Charge injection from the switch-control signal causes a voltage error at the analog output.

Figure 6b. A typical track/hold function requires precise control of the analog switches.

Leakage

In addition to RON error unwanted leakage is another parameter affecting the static (ON-switch) and dynamic (Off-switch) behaviours. Figure 7a/b shows a simplified small-signal-model for the ON-/Off-state. In both switching states leakage current occurs on internal and external (unmatched) parasitic-diodes, increasing the error voltage. In On-state, if an input signal exceeds maximum supply voltage range parasitic diodes will inject current into the substrate and an increased current follows into the adjacent channel. The ON-state error voltage is specified in Equation 3. In Off-state the error voltage is calculated by Vout=ILeakage Ã- RLOAD. A solution for leakage is the n-channel "Body-snatcher" (Q11, Q12) shown in Figure 1b. Q11 and Q12 FETs eliminate the leakage. The Q11 FET ensures a constant source-to-body voltage by connecting its source to the Body of Q9, compensating for the modulation. The designer should be aware of the Absolute Maximum Rating and must not exceed these limits. Exceeding the maximum value can permanently damage the device. The datasheet specifies leakage in worst case scenario, when signal voltage approaches the supply voltage limits. In addition, the leakage current is also a function of temperature and doubles approximately every 10°C.

Eq 3

Figure 7a.

Figure 7b.

Having reviewed these fundamentals, we now focus on innovative switches for special applications.

T-Switches for Higher Frequencies

In Video signals trade-off between RON and parasitic capacitance is important. Video switches with large RON need extra gain-stages at the output to compensate insertion loss (about 0.5dB), while low RON have large parasitic capacitance and reduces bandwidth thus degrading video quality. Low RON switches require input buffers for preserving the bandwidth but increases components. The minimum and maximum video frequencies (fmin, fmax) are mainly affected by large capacitance. The Bandwidth of a video switch must meet the Nyquist (2 Ã- fmax) requirement, in practice it is 3-6 times of fmax.

Employing only n-channel switches improves bandwidth as parasitic components and package size become smaller, allowing more switches per unit area. However, N-channel switches suffer from a limited rail-to-rail operation up to a certain value of VINmax (which is lower than VDD). When an applied video signal exceeds VINmax the output clamps while distorting the luminance and chrominance components. When selecting a n-channel switch, ensure that the signal range is sufficient passing through the maximum input signal.

Video switches require multiplexing several video signals. Often (in security and surveillance system) a signal monitor displays many video sources, high off-isolation and crosstalk are a key parameters for such application. In a turned off switch the amount of feedthrough of an applied input signal determine the Off-isolation. This parameter increases about 20dB per decade when operating in higher frequencies. The T-switch topology is suitable for video and other frequencies above 10MHz. It consists of two analog switches in series, with a third switch connected between ground and their joining node. This arrangement provides higher off-isolation than a single switch. The capacitive crosstalk for a T-switch turned off typically rises with frequency due to the parasitic capacitances in parallel with each of the series switches (Figure 8a). The problem in operating a high-frequency switch does not lie in turning it on, but in turning it off.

When the T-switch is turned on, S1 and S3 are closed and S2 is open. In the off state, S1 and S3 are open and S2 is closed. In that case (the off state) the signal tries to couple through the off-capacitance of the series MOSFETs, but is shunted to ground by S3. If you compare the off isolation at 10MHz for a video T-switch (MAX4545) and a standard analog switch (MAX312), the result is dramatic: -80dB versus -36dB for the standard switch (Figure 8b).

Maxim offer video switches that are buffer or unbuffered. As mentioned standard video switches (Passive video switches) may require additional buffer/gain circuit; the integrated approach (Active video switches) combine switch and buffer in one package (the MAX4310, for example). The integrated multiplexer-amplifiers have significant off-isolation for most NTSC and PAL systems (the MAX4310, for example).

(b)

Figure8. The T-switch configuration attenuates RF frequencies that couple through the stray capacitance between the source and the drain of an open (off) switch.

Smaller Packages

Other advantages for CMOS analog switches include small packages, such as the tiny 6-bump UCSP, and no mechanical parts (unlike reed relays). UCSP package reduces thermal dissipation by using bumps soldering technology than packages with exposed pads, but you should be aware that this package is mechanically not as robust as other packages. Mechanically more robust package is the SOT23. Maxim offers small low-voltage SPDT standard switches (for example the MAX4698 and MAX4688). Both come in come in 6-pin UCSP packages and operate from supply voltage ranges in the 2V to 5.5V and 1.8V to 5.5V, respectively. The MAX4698 and MAX4688 are the smallest SPDT analog switches currently available with tiny package dimensions of 1.5mm2. See Table 3.

Table 3. Small packages

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Flatness (Ω,max)

tON/tOFF(ns,max)

Charge Injection (pC,max)

Off-Osolation (dB max &typ)/Freuqency (MHz)

Supply Voltage Range (V)

Pin-Package

Package Size (mm2)

MAX4698

1 SPDT

35

0.5

13

80/25

8

-75/0.1

+2 to +5.5

6-UCSP

1.5

MAX4688

1 SPDT

2.5

0.5

1

30/12

40

-90/0.1

+1.8 to +5.5

6-UCSP

1.5

MAX4594

1 SPST; NO

10

0.5

1.5

35/40

5

-80/1

+2 to +5.5

6-µDFN

1.6

MAX4706/MAX4707

1 SPST; NC/NO

3

1

0.85

20/15

5

-82/1; -62/10

+1.8 to +5.5

6-µDFN

1.6

MAX4729/MAX4730

1 SPDT

5.5

2

0.95

45/26

3

-67/1; -45/10

+1.8 to +5.5

6-µDFN

1.6

MAX14508E/MAX14509AE/MAX14510E

1 DPDT; Bi-Directional

5

10000

-

60000/5000

-

-

+2.7 to +5

10-UTQFN

2.5

MAX14535E/MAX14536E

1 DPDT; NO

0.35

10

0.001

90000/40000

-

70/-

+2.4 to +5.5

10-UTQFN

2.5

MAX4992/MAX4993

2 SPDT/ 1 DPDT

0.5

100

-

150000/2000

-

-90/0.02

+1.8 to +5.5

10-UTQFN

2.5

MAX4719

2 SPDT

20

0.5

1.2

80/40

18

-80/1; -55/10

+1.8 to +5.5

10-UCSP

3.3

MAX14531E/MAX14532E

2 SP3T

2

2000

0.1

250000/6000

-

65/-

+2.7 to +5.5

12-WLP

3.3

MAX14504/MAX14505A

2 SPDT; Bi-Directonal- NO

0.5

50

0.001

60000/3000

-

84/-

+2.3 to +5.5

12-WLP

3.3

MAX4906/MAX4906F

2 SPDT; NO-NC

8

1000

1

60/30

6

-60/10; -26/500

+3 to +3.6

10-µDFN

4.2

MAX4754

4 DPDT

0.85

3

0.4

140/50

50

-65/0.1

+1.8 to +5.5

16-UCSP

4.3

MAX4501/MAX4502

1 SPST; NO/NC

250

1

-

75/10

10

-100/0.1

+2 to +12

5-SC70

5.3

MAX4624/MAX4625

1 SPDT

1

2

0.12

50/65

65

-57/1

+1.8 to +5.5

6-TSOT

8.3

MAX4514/MAX4515

1 SPST; NO/NC

20

1

3

150/100

10

-90/0.1

+2 to +12

5-SOT

9

MAX14550E

2 SP3T

6.5

250

-

100000/5000

-

-

+2.8 to +5.5

10-TDFN-EP

9.6

MAX4908/MAX4930

2 SP3T

0.8

-

0.35

-

-

-80/0.02

+1.8 to +5.5

14-TDFN-EP

9.6

As mentioned earlier, Maxim offers many variations of popular analog switches like the DG411, including a family of 70V quad analog switches (MAX14756-MAX14758). The MAX14756 is an improvement over the industry-standard 411, with higher analog-signal range (VSS to VDD) and higher accuracy: channel matching to within 0.5Ω maximum and channel flatness to 0.004Ω typically. This family of parts offers three switch configurations, and their lower on-resistance (<10Ω at ±20V) suits industrial and battery management applications. A tiny 16-pin TSSOP package solves the problem of board space.

ESD-Protected Switches

Change to newer parts?

As electrical overstress (EOS) and electrostatic discharge (ESD) can damage electronic circuits and components. Maxim offer many switches with ±15kV ESD protection bases on the IEC 6100-4-2 model (Table 4). All analog inputs are ESD-tested using the Human Body Model, as well as the Contact and Air-Gap Discharge methods specified in IEC 61000-4-2. The MAX4551/MAX4552/MAX4553 switches are pin-compatible with many standard quad-switch families such as the DG201/211 and the MAX391 types. To augment standard multiplexer families like the 74HC4051, MAX4581 and the MAX4927, Maxim also released ESD-protected multiplexers. You no longer need to use costly TransZorbs® to protect your analog inputs.

Table 4. ±15k ESD per IEC 1000-4-2/ IEC 61000-4-2 standard

Part Number

Function

Ron (max) (Ω)

Icom(off)/ID(off) (nA max)

ΔRon (max) (Ω)

Rflat(on) (max) (Ω)

ton/toff (ns max)

Charge Injection (pC typ)

Off-Isolation/Crosstalk (dB)

Supply Voltage Range (V)

MAX14535E/MAX14536E

1 DPDT; NO

0.35

±10

0.05

0.001

90000/40000

-

-70/-80 (@ ?MHz)

+2.4 to +5.5

MAX4983E/MAX4984E

1 DPDT; Bi-Directional

10

±250

1

0.1

100000/5000

-

-48/-73 (@10MHz)

+2.8 to +5.5

MAX4927

7 4:1 MUX; NO

5.5

±1000

1.5

0.01

50/50

-

-/-50 (@25MHz)

+3 to +3.6

MAX4575/MAX4577

2 SPST; NO/NO-NC

70

±0.5

2

4

150/80

4

-75/-90(@1MHz)

+2 to +12

MAX4620

4 SPST; NO

70

±0.5

2

4

150/80

5

-75/-90 (@1MHz)

+2 to +12

MAX4561

1 SPDT

70

±0.5

2

4

150/80

17

75/- (@1MHz)

+1.8 to +12

MAX4568/MAX4569

1SPST; NO/NC

70

±0.5

2

4

150/80

6

75/- (@1MHz)

+1.8 to +12

MAX4558/MAX4559/MAX4560

1 8:1 MUX/ 2 4:2 MUX/3 SPDT

160

±1

6

8

150/120

2.4

-96/-93 (@0.1MHz)

±2 to ±6 or +2 to +12

MAX4551/MAX4552/MAX4553

4 SPST; NC/NO/NO-NC

120

±1

4

8

110/90

2

-90/-90 (@0.1MHz)

±2 to ±6 or +2 to +12

Fault-Protected Switches

As mentioned under "Signal Handling" above, the supply-voltage rails for an analog switch restrict the allowed range for input signal voltage. Normally this restriction is not a problem, but in some cases the supply voltage can be turned off with analog signals still present. That condition causes devices to latch-up and permanently damage the switch, as can transients outside the normal range of the power supply. Other causes of latch-up are improper supply voltage sequencing (Vdd=Vss=0V) and supply voltage exceeding the absolute maximum ratings. For improper sequencing the most positive voltage should be applied first followed by lower voltage and the most negative at last. Some switches do not require power supply sequencing the multiplexer MAX14752, for example. This device can operate with high-voltage power supply (72V) and internal diodes at the inputs protect the switch from over- and under-voltages. Additional fault protection methods are employing a series resistor at the input limiting the current flow into the diodes, and adding two extra diodes (D1, D2) in series with the supplies. Disadvantage of D1 and D2 is limiting the input range by the forward-bias voltage of the diodes (Figure 9a). See application note "Low-Voltage Fault Protection" on more discussion. The MAX14752 is pin compatible with industry-standard DG408/DG409.

Figure 9a

Most Maxim's fault-protected switches and multiplexers guarantee overvoltage protection of ±25V and power-down protection of ±40V, along with rail-to-rail signal handling and the low on-resistance of a normal switch (Figure 9b). The input pin, moreover, assumes a high impedance during fault conditions regardless of the switch state or load resistance. Only nanoamperes of leakage current can flow from the source.

Figure 9b This internal structure shows the special circuitry in a fault-protected analog switch.

If the switch (P2 or N2) is on, the COM output is clamped to the supply by two internal 'booster' FETs. Thus, the COM output remains within the supply rails and delivers a maximum of ±13mA depending on the load, but without a significant current at the NO/NC pin. The fault-protected switches, MAX4511/MAX4512/MAX4513, are pin-compatible with the DG411-DG413 and DG201/DG202/DG213 types (Table 5). Note that signals pass equally well in either direction through an ESD- and fault-protected switch, but these protections apply only to the input side. Recent fault-protected Maxim switches have a flatter architecture, as these devices employ only two parallel FETs (the MAX4708, for example) instead of the four FETs shown in Figure 9b. During a fault condition the COM output of the MAX4708 is disconnected and becomes high impedance.

Table 5. Fault Protection with rail-to-rail signal swings

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Match(Ω,max)

Overvoltage Supplies ON/OFF (V)

tON/tOFF(ns,max)

Charge Injection (pC,max)

Supply Voltage Range (V)

Pin-Package

MAX9940

1 Line Protector

77.5

 

-

±28

-

-

+2.2 to +5.5

5-SC70

MAX4505

1 Line Protector

100

±0.5

-

±36/±40

-

-

+8 to +18 or ±9 to ±36

5-SOT; 8-µMAX

MAX4506

3Line Protector

100

±0.5

-

±36/±40

-

-

+8 to +18 or ±9 to ±36

8-CDIP(N)/PDIP(N)/SOIC(N)

MAX4507

8 Line Protector

100

±0.5

-

±36/±40

-

-

+8 to +18 or ±9 to ±36

18-PDIP(N)/SOIC(W); 20-SSOP

MAX4708/MAX4709

1 8:1 MUX/2 4:1 MUX

400

±0.5

15

±25/±40

275/200

0

+9 to +36 or ±4.5 to ±20

16-PDIP(N)/SOIC(N)

MAX4534/MAX4535

1 2:1 MUX; 2 4:1 MUX

400

±2

10

±25/±40

275/200

10

+9 to +36 or ±4.5 to ±18

14-PDIP(N)/SOIC(N)/TSSOP

MAX4533

4 SPDT

175

±0.5

6

±25/±40

250/150

1.5

+9 to +36 or ±4.5 to ±18

20-PDIP(N)/SOIC(W)/SSOP

MAX4508/MAX4509

1 8:1 MUX/2 4:1 MUX

400

±0.5

15

±25/±40

275/200

10

+9 to +36 or ±4.5 to ±20

16-CDIP(N)/PDIP(N)/SOIC(N)

MAX4632

2 SPDT

85

±0.5

6

±25/±40

500/400

10

+9 to +36 or ±4.5 to ±18

16-PDIP(N)/SOIC(N)

MAX4510/MAX4520

4 SPST; NC/NO

75

±0.5

-

±36/±40

500/175

5

+9 to +36 or ±4.5 to ±20

8-µMAX; 6-SOT

MAX4633

2 DPST; NO

85

±0.5

6

±36/±40

500/400

10

+9 to +36 or ±4.5 to ±18

16-PDIP(N)/SOIC(N)

MAX4511/MAX4512/MAX4513

4 SPST; NC/NC/NO-NC

160

±0.5

6

±36/±40

500/400

5

+9 to +36 or ±4.5 to ±20

16-CDIP(N)/PDIP(N)/SOIC(N)

MAX4711

4 SPST; NC

25

±0.5

1

±7/±12

125/80

25

+2.7 to +11 or ±2.7 to ±5.5

16-PDIP(N)/SOIC(N)/TSSOP

Force-Sense Switches

Maxim offers a family of analog switches with different switch types residing in the same package. The MAX4554/MAX4555/MAX4556 devices, for instance, are configured as force-sense switches for Kelvin sensing in automated test equipment (ATE). Each part contains low-resistance high-current switches for forcing current and higher-resistance switches for sensing voltage or switching guard signals. On-resistance for the current switches is only 6Ω, and for the sensing switches is 60Ω at ±15V supply voltages. The MAX4556 contains three SPDT switches with break-before-make action.

Typical force-sense applications are found in high-accuracy systems and in measurement systems that involve long distances (Figure 10). For 4-wire measurements, two wires force a voltage or current to the load, and two other wires connected directly to the load sense the load voltage.

Figure 10. With the 4-wire technique, two wires force and two other wires sense the measured voltage.

Alternatively, a 2-wire system senses load voltage at the ends of the force wires opposite the load. Load voltage is lower than the source voltage, because the forcing voltage or current causes a voltage drop along the wires. Longer distance between source and load, larger load current, and higher conductor resistance all contribute for this degradation. The resulting signal reduction can be overcome by using a 4-wire technique in which the two additional voltage-sensing conductors carry negligible current.

Force-sense switches simplify many applications, such as switching between one source and two loads in a 4-wire system. They are suitable for use in high-accuracy measurement systems, such as nanovoltmeters and femtoammeters, and for 8- or 12-wire force-and-sense measurements using the guard wires of triax cables. For more information, please see the MAX4554/MAX4555/MAX4556 data sheet.

Multiplexers

In addition to switches, Maxim makes a number of multiplexers (MUXes). A MUX is a special version of a switch in which two or more inputs are selectively connected to a single output. A MUX can be as simple as an SPDT switch or come in 2:1, 4:1, 8:1, 16:1 combinations for different channel of 1,2,4,7 and 8. The digital control for these higher order MUXes is similar to a binary decoder with three digital inputs required to select the appropriate channel.

A demultiplexer is basically a MUX used backwards. That is, one input connects to two or more outputs based on the decoded address data.

There are, finally, cross-point switches that are employed in audio/video routing, video on demand, security and surveillance systems. A cross-point switch is usually an M x N device, whereby any or all of M inputs may be connected to any or all of N outputs (and vice versa).

For instance, the buffered 32x16 crosspoint switch MAX4358 comes in a space saving 144-pin TQFP package, which is comparable with 512 T-switches. The MAX4358 is capable of implementing larger matrixes, an example of a 128x32 non-blocking matrix is shown in Figure 11a. The number of ICs required are a function of number of input channels, the number of output channels and whether the array is non-blocking or has switching constraints. The inputs of each MAX4358 in Bank 1 are parallel connected to Bank 2. The vertical output of each Bank is a wired-OR configuration of all four MAX4358 devices. This wired-OR configuration is possible due to IC's output buffers that can be selected in disabled or high-impedance output state, while maintaining low output capacitance the adverse loading is minimized from disabled outputs.

This technique allows larger matrixes to be constructed by connecting more devices; however it requires connecting many outputs together. As a result, the output node of each Bank sees two impedance loads, the normal and disabled impedance loads. The disabled impedance loads of all the other outputs has resistive and capacitive components. The MAX4358 output buffer compensates for the resistive component but in some cases the capacitance increases (>30pF) in larger matrixes, as the PC-board traces become longer. One solution is to reduce the number wired-OR connection of each output node by increasing more crosspoint switches per Bank shown in Figure 11b. Another method is putting a small (5Ωto 30Ω) resistor in series with the output but drawback is a lowpass filter response with the parasitic capacitance. This is often a problem in large systems as the cumulative effect of many cascaded R-Cs form a roll-off at higher frequencies causing "softening" of the picture. Solution to this constrain is by routing the output PC board traces in repeating "S" configuration so that they exhibit some impedance. The Traces closest to each other exhibit mutual impedance that increases the total inductance. Series impedance increases the magnitude response at higher frequencies, compensating for the "Softening" effect. The second solution is adding a small inductor at the output but optimum solution is a combination of both approaches.

Some critical crosspoint switch parameters are cost, package size and crosstalk between channels. Maxim offer a wide range of crosspoint switches such as the 8x4 array MAX4360 a replacement product for the MAX458; see Table 6 for some of the Maxim's crosspoint switches.

(b)

Figure 1

Table 6. Crosspoint switches

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Match(Ω,max)

RON Flatness (Ω,max)

tON/tOFF(ns,max)

Off-Isolation (dB)

Crosstalk (dB)

-3dB Bandwidth (MHz)

Supply Voltage Range (V)

Pin-Package

Package Size (mm2)

MAX4989

2 2-of-4 Bidirectional switch

9

±1

0.5

0.4

100000/6000

-43dB (@10MHz)

-50dB (@50MHz)

1000

+2.7 to +5.5

14-TDFN-EP

9.6

MAX4548/MAX4549

3 x 3:2

35

±2

7

5

400/200

-72dB (@10MHz)/-85dB (@20kHz)

-55dB (@10MHz)/-85dB (@20kHz)

250

+2.7 to +5.5

36-SSOP

163.4

MAX4550/MAX4570

2 x 4:2

80

±5

10

5

900/500

-78dB (@4MHz)

-54dB (@4MHz)

-

+2.7 to +5.5 or ±2.7 to ±5.5

28-SOIC(W)/SSOP

192.8

MAX9675

16x16

-

-

-

-

-

-110dB (@6MHz)

-62dB (@6MHz)

110

±5

100-TQFP

262.4

MAX4355

16x16

-

-

-

-

-

-110dB (@6MHz)

-62dB (@6MHz)

110

+5 or ±3 or ±5

100-TQFP

262.4

MAX4357

32x16

-

-

-

-

-

-110dB (@6MHz)

-62dB (@6MHz)

110

+5 or ±3 or ±5

128-LQFP

359.6

MAX4356

16x16

-

-

-

-

-

-110dB (@6MHz)

-62dB (@6MHz)

110

+5 or ±3 or ±5

128-LQFP

359.6

MAX4358

32x16

-

-

-

-

-

-110dB (@6MHz)

-62dB (@6MHz)

110

+5 or ±3 or ±5

144-TQFP

492.8

MAX4359

4x4

-

-

-

-

-

-80 (5MHz)

-70 (5MHz)

35

±5

24SOIC(W)/36-SSOP

163.4

MAX4360

8x4

-

-

-

-

-

-80 (5MHz)

-70 (5MHz)

35

±5

36-SSOP

163.4

MAX4456

8x8

-

-

-

-

-

-80 (5MHz)

-70 (5MHz)

35

±5

40-PDIP(W)/44-PLCC

311.5

Calibration Multiplexers

Calibration multiplexers (cal-MUXes) are used in precision ADCs and other self-monitoring systems. They combine different components in one package: analog switches for generating accurate voltage ratios from an input reference voltage; internal precision resistor-dividers; and a multiplexer for selecting between different inputs. Maxim introduced this combination of functions in a single package.

Four of these devices (MAX4539, MAX4540, MAX4578 and MAX4579) can balance two major errors associated with an ADC system: offset and gain error. Using the internal precision voltage-dividers, these devices measure gain and offset in a few steps, controlled trough the serial interface of a microcontroller. The reference ratios 15/4096 and 4081/4096 (with respect to the external reference voltage) are accurate to 15 bits. The ratios (5/8)(V+ - V-) and V+/2 are accurate to 8 bits.

The cal-MUX first applies one-half the supply voltage to verify that power is present. The system then measures zero offset and gain error, and forms an equation to correct the subsequent readings. Zero input voltage, for example, should produce a digital zero output. The cal-MUX calibrates for offset error by applying a very small input voltage of 15/4096 referred to (VEFHI - REFLO). For a 12-bit ADC with 4.096V reference, 15/4096 equals 15mV and also 15 LSBs. The digital output therefore should be binary 000000001111. To measure offset error, the microcontroller simply records the difference between binary 000000001111 and the ADC's actual output.

To measure gain error, the cal-MUX applies a voltage of 4081/4096 referred to (VREFHI - VREFLO). The microcontroller then records the difference between binary 111111110000 and the ADC's digital output. Knowing the ADC's offset and gain error, the system software constructs calibration factors that adjust the subsequent outputs to produce correct readings. The cal-MUX then serves as a conventional multiplexer, but with the ability to recalibrate the system periodically.

USB 2.0 Switches

A universal serial bus (USB) is a high-speed interface for handheld devices to communicate with computers. Multiple USB devices can be connected to a computer, and analog switches are used to route the USB signal to different devices. The USB 2.0 is a high-speed signal that requires a high-bandwidth and low-capacitance analog switch. The MAX14531E, for example provides low CON and RON and for extremely high performance switching. Additional features are ESD protection, negative signal capability (up to -2V) and integrated Click-and-Pop switched shunt resistor. Some USB switches combine USB host data and charger into one interface (the MAX14550E, for example).

Maxim offers a good selection of USB 2.0-compliant switches ideal for USB 2.0 high-speed applications (480Mbs). Table 7 shows a few examples of USB 2.0 switches. Based on the success of Maxim's 2.0 USB switches, the MAX14972 a 3.0 USB product will be soon available, allowing data rates up to 5GHz. Register in the Link to be notified when full data sheet is available.

Table 7. USB 2.0 switches

Part Number

Function

RDS(ON)(Ω,max)

RON Match(Ω,max)

RON Flatness (Ω,max)

tON/tOFF(ns,max)

ICOM(OFF)/ID(OFF) (nA,max)

Con / Coff (pF,typ)

Charge Injection (pC,max)

BW (MHz)

Supply Voltage Range (V)

MAX14578E

2 SPST; NO

-

-

-

-

-

-

-

-

+2.8 to +5.5

MAX14508E/MAX14509AE/HYPERLINK "http://www.maxim-ic.com/datasheet/index.mvp/id/5886"MAX14510E

1 DPDT; Bi-Directional

5

-

-

60000/5000

10000

8/8

-

950

+2.7 to +5

MAX14550E

2 SP3T

6.5

-

-

100000/5000

250

5.5/2

-

1000

+2.8 to +5.5

MAX14531E/MAX14532E

2 SP3T

2

-

0.1

250000/6000

2000

8/5

-

800

+2.7 to +5.5

MAX4999

8 8:1 MUX

12

0.8

-

10000/10000

1000

6/5

-

1200

+3 to +3.6

MAX4983E/MAX4984E

1 DPDT; Bi-Directional

10

1

0.1

100000/5000

250

6.5/5.5

-

950

+2.8 to +5.5

MAX4906/MAX4906F

2 SPDT; NO-NC

7

1.2

1

60/30

1000

6/2

5

1000

+3 to +3.6

MAX4907/MAX4907F

2 SPST; NO

7

1.2

1

60/30

1000

4/2

5

1000

+3 to +3.6

MAX4906EF

2 SPDT; NO-NC

5

0.8

0.5

1.4/35

1000

10/9

20

500

+3 to +3.6

MAX4899AE/MAX4899E

4:1 MUX/ 3:1 MUX

5

0.8

1.1

2800/3

1000

15/10.5

25

425

+2.7 to +3.6

HDMI Switches

A High-Definition Multimedia Interface (HDMI) is a high-speed interface for all-digital audio/video signalling. In latest HDTVs, DVD players and digital video application HDMI standard has replaced the VGA and component video standards.

Maxim offers good selection of HDMI switches for v1.3 and v.1.4 (the MAX14886, for example). Table 8 shows a few examples of HDMI switches.

Table 8. HDMI switches

Part Number

Function

RDS(ON)(Ω,typ)

RON Match(Ω,typ)

RON Flatness (Ω,max)

Off-Isolation (dB)

Crosstalk (dB)

BW (MHz)

Supply Voltage Range (V)

MAX14886

4 2:1 Switch; NO-NC

-

0.28

-

-

-

5000

+3 to +3.6

MAX4814

1 2:4 Switch; Bi-Directional

12

-

2.5

65 (@ 1MHz)

75 (@ 1MHz)

190

+4.5 to +5.5

MAX4929E

2 2:1 MUX; NO-NC

10

2

13

70 (@ 1MHz)

75 (@ 1MHz)

40

+5 or ±5

MAX4886

4 2:1 Switch; NO-NC

8

0.28

0.6

58 (@ 50MHz)

-49 (@ 50MHz)

2600

+3 to +3.6

High-Voltage Switches

In ultrasound applications, high-voltage pulses (±100V) are applied to transducers to generate ultrasonic waves. Analog switches are required for routing these high-voltage signals between the transducers and the main systems, so the switches must be able to handle high-voltage signals.

Maxim offers a good selection of high-voltage analog switches that are ideal for ultrasound medical applications. Table 9 shows a few examples.

Table 9. High-voltage switches

Part Number

Function

Single Vsupply (min,V)

Single Vsupply (max,V)

Dual Vsupply (min,±V)

Dual Vsupply (max,±V)

BW (MHz)

ICOM(OFF)/ID(OFF) (nA,max)

tON/tOFF(ns,max)

Con / Coff (pF,typ)

MAX14802/MAX14803/MAX14803A

16 SPST; NO

-

200

40

160

50

2000

5000/5000

36/11

MAX4800A/MAX4800B

8 SPST; NO

40

200

40

100

20

2000

5000/5000

36/11

MAX4802A

8 SPST; NO

40

200

40

100

50

2000

5000/5000

36/11

DisplayPort/PCIe switches

A Peripheral Component Interconnect Express (PCIe) is a point-to-point Input/Output interconnect bus standard for higher data rates (10Gbps) over the original PCI. The PCIe backplane bus is becoming popular for many system designs. PCIe switches are used in real-time Hot-Plug systems, in laptop expansion card interfaces, Scaled Link Interface (SLI) and Crossfire. These switches facilitate high isolation and point-to-point connection thus reducing system errors.

Maxim offers switches that support PCIe Gen I, Gen II and Gen III data rates using CMOS technology. The MAX4928A/MAX4928B are two hex double-pole/double-throw (6 DPDT) analog switches designed to handle PCIe/DisplayPort switching Table 10 shows more selections of PCIe switches.

Table 10. PCIe switches

Part Number

Function

RDS(ON)(Ω,max)

ICOM(OFF)/ID(OFF) (nA,max)

RON Match(Ω,max)

tON/tOFF(ns,max)

Off. Iso. (dB)

Crosstalk (dB)

BW (MHz)

Supply Voltage Range (V)

Pin-Package

Package Size (mm2)

MAX4888B/MAX4888C

2 1:2 MUX; Bi -Directional

8

1000

0.5

-

12

30

8000

+3 to +3.6

28-TQFN

20.2

MAX4889B

1:2 Switch; Bi -Directional

8.4

1000

0.5

-

12

30

5000

+3 to +3.6

42-TQFN

32.8

MAX4928A/MAX4928B

6 1:2 Switch; Bi-Directional

-

8

2

120/50

22

40

10000

+3 to +3.6

56-TQFN

56.6

MAX4888A/MAX4889A

4 SPDT/8 SPDT; Bi-Directional

8.4

1000

1

250/50

12

-56

5000

+1.6 to +3.6

28-TQFN

20.2

MAX4888/MAX4889

4 SPDT/8 SPDT; NO-NC

7

-

1

250/50

26

32

1250

+1.6 to +3.6

28-TQFN

20.2

µMAX is a registered trademark of Maxim Integrated Products, Inc.

TRANSZORB is a registered trademark of Vishay General Semiconductor, LLC.

UCSP is a trademark of Maxim Integrated Products, Inc.

HDMI is a registered trademark and registered service mark of HDMI Licensing LLC.

PCI Express is a registered service mark of PCI-SIG Corporation.

PCIe is a registered service mark of PCI-SIG Corporation.

SLI is a registered trademark of NVIDIA.

Crossfire is a registered trademark of AMD Graphics Product Group.

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