19-4457; Rev 0; 2/09 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals Features The MAX9541/MAX9542 are quadruple-channel, 2:1 video mux amplifiers with input sync tip clamps. These devices select between two video sources and support up to four channels on each source. The MAX9541 has integrated lowpass filters that are optimized for standarddefinition video signals such as composite and red, green, blue (RGB). The filters typically have ±1dB passband flatness out to 9.5MHz and 47dB attenuation at 27MHz. The MAX9542 has a wider bandwidth of 15MHz because it does not have integrated lowpass filters, making it suitable for not only standard-definition video signals, but also video graphics array (VGA) signals with a 640 x 480 resolution at up to 85Hz refresh rate. Video signals are AC-coupled to the inputs of the MAX9541/MAX9542. The input sync-tip clamps set the internal DC level. The amplifiers have 2V/V gain, and the outputs can be DC-coupled to a 75Ω load, which is the equivalent of two video loads, or AC-coupled to a 150Ω load. Both the MAX9541/MAX9542 feature a low-power shutdown mode, in which supply current is reduced to 35µA. ♦ Quad 2:1 Video Mux Amplifiers ♦ Reconstruction Filters with 9.5MHz Passband and 47dB Attenuation at 27MHz (MAX9541) ♦ Fixed Gain of 2V/V ♦ Input Sync-Tip Clamps ♦ Shutdown ♦ 2.7V to 3.6V Single-Supply Operation Ordering Information PART PIN-PACKAGE MAX9541AEE+ 16 QSOP STANDARDDEFINITION VIDEO FILTER Yes No Note: All devices are specified over the -40°C to +125°C operating temperature range. MAX9542AEE+ 16 QSOP +Denotes a lead(Pb)-free/RoHS-compliant package. Applications Automotive Infotainment Functional Diagram VDD SHDN A/B MAX9541 MAX9542 0 IN0A LPF* 2V/V OUT0 1 IN1A CLAMPREF UNKNOWN BIAS 0 300mV IN2A IN3A 1 LPF* 2V/V LPF* 2V/V LPF* 2V/V OUT1 CLAMPREF 0 IN0B 1 OUT2 IN1B CLAMPREF 0 IN2B 1 IN3B OUT3 CLAMPREF GND *LOWPASS FILTER IN MAX9541 ONLY. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX9541/MAX9542 General Description MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals ABSOLUTE MAXIMUM RATINGS Supply Voltage VDD to GND ..........................................................-0.3V to +4V Input Pins, SHDN, A/B .............................(GND - 0.3V) to +4V Duration of Output Short Circuit to VDD or GND ........Continuous Continuous Input Current Input Pins......................................................................±20mA Continuous Power Dissipation (TA = +70°C) 16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX 2.7 UNITS Supply Voltage Range VDD Guaranteed by power-supply rejection test 3.3 3.6 V Quiescent Supply Current IDD No load 21 45 mA Shutdown Supply Current ISHDN SHDN = A/B= GND 35 70 μA Input Voltage Unselected input VDD/3 V Input Resistance Unselected input 222 kΩ Sync-Tip Clamp Level VCLP 0.23 Sync Crush 2.7V ≤ VDD ≤ 3.6V 1.05 1.2 Input Clamping Current 1 Maximum Input Source Resistance 300 DC Voltage Gain (Note 2) AV DC Gain Mismatch Output Short-Circuit Current 2 ROUT V VP-P 2 % 2 µA Ω VDD = 2.7V, 0V ≤ VIN ≤ 1.05V 1.96 2 2.04 VDD = 3V, 0V ≤ VIN ≤ 1.2V 1.96 2 2.04 Measured at VOUT, CIN_ = 0.1µF to GND Output Voltage Swing Output Resistance RL = 150Ω to GND (Note 2) Guaranteed by DC voltage gain Output Level 0.39 3.0V ≤ VDD ≤ 3.6V Sync-tip clamp; percentage reduction in sync pulse (0.3VP-P); guaranteed by input clamping current measurement Guaranteed by DC voltage gain Input Voltage Range 0.3 V/V -2 0.218 0.3 Measured at output, VDD = 2.7V, VIN = VCLP to (VCLP +1.05V), RL = 150Ω to -0.2V 2.1 Measured at output, VDD = 2.7V, VIN = VCLP to (VCLP +1.05V), RL = 150Ω to VDD/2 2.1 Measured at output, VDD = 3.0V, VIN = VCLP to (VCLP +1.2V), RL = 150Ω to -0.2V 2.4 Measured at output, VDD = 3.0V, VIN = VCLP to (VCLP +1.2V), RL = 150Ω to VDD/2 2.4 Measured at output, VDD = 3.135V, VIN = VCLP to (VCLP +1.05V), RL = 75Ω to -0.2V 2.1 Short to GND (sourcing) 140 Short to VDD (sinking) 70 VOUT = 1.5V, -10mA ≤ ILOAD ≤ +10mA 0.2 _______________________________________________________________________________________ +2 % 0.39 V VP-P mA Ω Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS 2.7V ≤ VDD ≤ 3.6V Power-Supply Rejection Ratio MIN 48 f = 100kHz, 100mVP-P TYP MAX 64 UNITS dB 20 Small-Signal Bandwidth VOUT = 100mVP-P (MAX9542 only) 27 MHz Large-Signal Bandwidth VOUT = 2VP-P (MAX9542 only) 15 MHz Slew Rate MAX9542 only 65 V/μs Settling Time Settled to within 0.1% of final value (MAX9542 only) 75 ns VOUT = 2VP-P, reference frequency is 100kHz, ±1dB passband flatness (MAX9541 only) 9.5 MHz Standard-Definition Reconstruction Filter VOUT = 2VP-P, reference frequency is 100kHz (MAX9541 only) f = 5.5MHz 0.1 f = 9.5MHz -1 f = 10MHz -3 f = 27MHz -47 Differential Gain DG 5-step modulated staircase of 129mV step size and 286mV peak-to-peak subcarrier amplitude, f = 4.43MHz Differential Phase DP 5-step modulated staircase of 129mV step size and 286mV peak-to-peak subcarrier amplitude, f = 4.43MHz dB 0.4 % 0.45 deg Group-Delay Distortion 100kHz ≤ f ≤ 5MHz, outputs are 2VP-P 9 ns Peak Signal to RMS Noise 100kHz ≤ f ≤ 5MHz 71 dB 2T Pulse Response 2T = 200ns 0.2 K% 2T Bar Response 2T = 200ns; bar time is 18μs; the beginning 2.5%, and the ending 2.5% of the bar time is ignored 0.2 K% 2T Pulse-to-Bar K Rating 2T = 200ns; bar time is 18μs; the beginning 2.5%, and the ending 2.5% of the bar time is ignored 0.3 K% Nonlinearity 5-step staircase 0.1 % Output Impedance f = 5.5MHz 8.07 Ω f = 15kHz -82 f = 4.43MHz -78 f = 30MHz -68 All-Hostile Crosstalk Output-to-Input Crosstalk dB dB LOGIC SIGNALS (TV_SEL, VCR_SEL, SHDN) Logic-Low Threshold VIL Logic-High Threshold VIH Logic-Input Current IIN 0.3 x VDD 0.7 x VDD V V 10 μA Note 1: All devices are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design. Note 2: Voltage gain (AV) is a two-point measurement in which the output-voltage swing is divided by the input-voltage swing. _______________________________________________________________________________________ 3 MAX9541/MAX9542 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (MAX9541) (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = +25°C.) 3 1 -2 -3 -30 -4 -35 -40 -45 -50 -6 -45 -50 -7 1M 10M 100M 100k VIDEO CROSSTALK vs. FREQUENCY VIDEO GROUP DELAY DISTORTION vs. FREQUENCY 0 VIN = 1VP-P GAIN IS NORMALIZED TO 0dB GROUP DELAY (ns) -20 0 -40 GAIN (dB) -1 -2 -3 -60 ALL-HOSTILE -80 -4 -5 120 110 100 90 MAX9541 toc05 1 2 ADJACENT CHANNELS -100 -6 -7 -120 100M 100k 1M VIDEO PSRR vs. FREQUENCY VOLTAGE GAIN vs. TEMPERATURE -30 -40 -50 MAX9541 toc08 2.02 2.01 1.99 1.98 -70 1.97 1.96 1M 10M FREQUENCY (Hz) 100M -50 -25 0 25 50 1M 100M 10M 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 75 100 125 f = 3.58MHz 0 2.00 -60 -80 40 30 20 DIFFERENTIAL GAIN 2.03 VOLTAGE GAIN (V/V) -20 50 FREQUENCY (Hz) 2.04 MAX9541 toc07 VDD = 3.3V + 100mVP-P -10 80 70 60 100k 100M 10M FREQUENCY (Hz) DIFFERENTIAL GAIN (%) 10M FREQUENCY (Hz) DIFFERENTIAL PHASE (deg) 1M VIN = 1VP-P GAIN IS NORMALIZED TO 0dB 10 0 1 ADJACENT CHANNEL 100k 100M 10M LARGE-SIGNAL GAIN FLATNESS vs. FREQUENCY VIN = 1VP-P GAIN IS NORMALIZED TO 0dB 100k 1M FREQUENCY (Hz) 2 4 10M FREQUENCY (Hz) 3 0 1M 100k 100M FREQUENCY (Hz) MAX9541 toc04 100k MAX9541 toc06 -5 -40 -10 -15 -20 -25 1 2 3 4 5 DIFFERENTIAL PHASE 0.8 0.6 0.4 0.2 0 -0.2 -0.4 f = 3.58MHz 0 1 2 TEMPERATURE (°C) _______________________________________________________________________________________ 3 4 5 MAX9541 toc09 -30 -35 -1 GAIN (dB) -25 VIN = 1VP-P GAIN IS NORMALIZED TO 0dB -5 0 -10 -15 -20 GAIN (dB) GAIN (dB) -5 GAIN (dB) VIN = 50mVP-P GAIN IS NORMALIZED TO 0dB 2 10 5 0 MAX9541 toc02 VIN = 50mVP-P GAIN IS NORMALIZED TO 0dB MAX9541 toc01 10 5 0 LARGE-SIGNAL GAIN vs. FREQUENCY SMALL-SIGNAL GAIN FLATNESS vs. FREQUENCY MAX9541 toc03 SMALL-SIGNAL GAIN vs. FREQUENCY PSRR (dB) MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals 2T RESPONSE 0 1 2 3 4 12.5T RESPONSE MAX9541 toc11 MAX9541 toc10 f = 4.43MHz MAX9541 toc12 IN 200mV/div IN 200mV/div OUT 400mV/div OUT 400mV/div 5 DIFFERENTIAL PHASE 0.8 0.6 0.4 0.2 0 -0.2 -0.4 f = 4.43MHz 0 1 2 3 4 100ns/div 400ns/div FIELD SQUARE WAVE VIDEO SYNC-TIP CLAMP VOLTAGE vs. TEMPERATURE 5 NTC-7 VIDEO TEST SIGNAL MAX9541 toc13 MAX9541 toc14 0.37 MAX9541 toc15 DIFFERENTIAL PHASE (deg) DIFFERENTIAL GAIN (%) DIFFERENTIAL GAIN 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 IN 500mV/div IN 500mV/div OUT 1V/div OUT 1V/div SYNC-TIP CLAMP VOLTAGE (V) 0.36 0.35 0.34 0.33 0.32 0.31 0.30 0.29 0.28 10μs/div -50 2ms/div -25 0 25 50 75 100 125 TEMPERATURE (°C) VIDEO SYNC-TIP CLAMP CURRENT vs. TEMPERATURE 1.00 0.98 0.96 0.94 0.92 0.90 300 200 100 0 -25 0 25 50 75 TEMPERATURE (°C) 100 125 21.5 21.0 20.5 20.0 19.5 19.0 18.5 18.0 -100 -50 MAX9541 toc18 400 22.0 QUIESCENT SUPPLY CURRENT (mA) 1.02 QUIESCENT SUPPLY CURRENT vs. TEMPERATURE MAX9541 toc17 1.04 500 SYNC-TIP CLAMP CURRENT (μA) MAX9541 toc16 SYNC-TIP CLAMP CURRENT (μA) 1.06 SYNC-TIP CLAMP CURRENT vs. INPUT VOLTAGE 0 0.2 0.4 0.6 0.8 1.0 INPUT VOLTAGE (V) 1.2 1.4 1.6 -50 -25 0 25 50 75 100 125 TEMPERATURE (°C) _______________________________________________________________________________________ 5 MAX9541/MAX9542 Typical Operating Characteristics (continued) (MAX9541) (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = +25°C.) Typical Operating Characteristics (continued) (MAX9542) (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = +25°C.) VIN = 50mVP-P GAIN IS NORMALIZED TO 0dB -5 -10 -15 1 0 -20 -25 -3 -40 -45 -6 -5 -7 10M 100M 100k 1M 10M FREQUENCY (Hz) FREQUENCY (Hz) LARGE-SIGNAL GAIN vs. FREQUENCY LARGE-SIGNAL GAIN FLATNESS vs. FREQUENCY 10 5 VIN = 1VP-P GAIN IS NORMALIZED TO 0dB 0 3 -5 -10 -15 100M VIN = 1VP-P GAIN IS NORMALIZED TO 0dB 2 1 MAX9541 toc22 1M MAX9541 toc21 100k 0 GAIN (dB) -20 -25 -30 -35 -1 -2 -3 -4 -5 -40 -45 -6 -50 -7 1M 10M 100M 100k 1M 10M FREQUENCY (Hz) FREQUENCY (Hz) VIDEO CROSSTALK vs. FREQUENCY VIDEO GROUP DELAY DISTORTION vs. FREQUENCY 0 -20 -40 -60 ALL-HOSTILE -80 100M 50 VIN = 1VP-P GAIN IS NORMALIZED TO 0dB 45 40 GROUP DELAY (ns) VIN = 1VP-P GAIN IS NORMALIZED TO 0dB MAX9541 toc23 100k MAX9541 toc24 GAIN (dB) -2 -4 -50 35 30 25 20 15 10 1 ADJACENT CHANNEL 5 2 ADJACENT CHANNELS -120 0 100k 1M 10M FREQUENCY (Hz) 6 -1 -30 -35 -100 VIN = 50mVP-P GAIN IS NORMALIZED TO 0dB 2 GAIN (dB) GAIN (dB) 0 3 MAX9541 toc19 10 5 SMALL-SIGNAL GAIN FLATNESS vs. FREQUENCY MAX9541 toc20 SMALL-SIGNAL GAIN vs. FREQUENCY GAIN (dB) MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals 100M 100k 1M 10M FREQUENCY (Hz) _______________________________________________________________________________________ 100M Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals VIDEO PSRR vs. FREQUENCY VOLTAGE GAIN vs. TEMPERATURE -10 2.03 VOLTAGE GAIN (V/V) -20 -30 -40 -50 MAX9541 toc26 VDD = 3.3V + 100mVP-P 2.02 2.01 2.00 1.99 -60 1.98 -70 1.97 -80 1.96 100k 1M 100M 10M -50 -25 0 FREQUENCY (Hz) 1 2 3 4 5 1 2 3 4 5 1 2 3 0.8 0.6 0.4 0.2 0.0 -0.2 -0.4 125 4 5 f = 4.43MHz 0 27 RESPONSE 1 2 3 4 5 12.5T RESPONSE MAX9541 toc29 100ns/div 100 f = 4.43MHz 0 f = 3.58MHz 0 0.10 0.05 0.00 -0.05 -0.10 -0.15 -0.20 DIFFERENTIAL PHASE (deg) DIFFERENTIAL PHASE (deg) 0 75 DIFFERENTIAL GAIN (%) DIFFERENTIAL GAIN (%) f = 3.58MHz 0.8 0.6 0.4 0.2 0.0 -0.2 -0.4 50 DIFFERENTIAL GAIN AND PHASE MAX9541 toc27 DIFFERENTIAL GAIN AND PHASE 0.10 0.05 0.00 -0.05 -0.10 -0.15 -0.20 25 TEMPERATURE (°C) MAX9541 toc28 PSRR (dB) 2.04 MAX9541 toc25 0 MAX9541 toc30 IN 200mV/div IN 200mV/div OUT 400mV/div OUT 400mV/div 400ns/div _______________________________________________________________________________________ 7 MAX9541/MAX9542 Typical Operating Characteristics (continued) (MAX9542) (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = +25°C.) Typical Operating Characteristics (continued) (MAX9542) (VDD = 3.3V, VGND = 0, SHDN = VDD, A/B = VDD, RL = 150Ω to GND, TA = +25°C.) NTC-7 VIDEO TEST SIGNAL FIELD SQUARE WAVE MAX9541 toc31 MAX9541 toc32 IN 500mV/div IN 500mV/div OUT 1V/div OUT 1V/div 10μs/div 2ms/div VIDEO SYNC-TIP CLAMP VOLTAGE vs. TEMPERATURE VIDEO SYNC-TIP CLAMP CURRENT vs. TEMPERATURE 0.35 SYNC-TIP CLAMP CURRENT (μA) 0.36 0.34 0.33 0.32 0.31 0.30 1.04 1.02 1.00 0.98 0.96 0.94 0.92 0.29 0.28 0.90 -50 100ns/div MAX9541 toc35 1.06 MAX9541 toc34 0.37 SYNC-TIP CLAMP VOLTAGE (V) INPUT (700mV/div) MAX9541 toc33 PULSE RESPONSE OUTPUT (700mV/div) -25 0 25 50 75 100 125 -50 -25 TEMPERATURE (°C) 300 200 100 0 50 MAX9541 toc37 21.5 21.0 20.5 20.0 19.5 19.0 18.5 18.0 -100 0 0.2 0.4 0.6 0.8 1.0 INPUT VOLTAGE (V) 8 22.0 QUIESCENT SUPPLY CURRENT (mA) 400 25 QUIESCENT SUPPLY CURRENT vs. TEMPERATURE MAX9541 toc36 500 0 1.2 1.4 1.6 75 TEMPERATURE (°C) SYNC-TIP CLAMP CURRENT vs. INPUT VOLTAGE SYNC-TIP CLAMP CURRENT (μA) MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals -50 -25 0 25 50 75 100 125 TEMPERATURE (°C) _______________________________________________________________________________________ 100 125 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals PIN NAME 1 IN0A Video Input A Channel 0 FUNCTION 2 IN1A Video Input A Channel 1 3 IN2A Video Input A Channel 2 4 IN3A Video Input A Channel 3 5 IN0B Video Input B Channel 0 6 IN1B Video Input B Channel 1 7 IN2B Video Input B Channel 2 8 IN3B Video Input B Channel 3 9 GND Ground 10 SHDN Shutdown Logic Input. Connect to GND to place the device in shutdown. Connect to VDD for normal operation. 11 OUT3 Video Output Channel 3 12 OUT2 Video Output Channel 2 13 OUT1 Video Output Channel 1 14 OUT0 Video Output Channel 0 15 A/B Input Select. Connect to GND to select Video Input A as the video source. Connect to VDD to select Video Input B as the video source. 16 VDD Positive Power Supply. Bypass to GND with a 0.1µF capacitor. Detailed Description The MAX9541 selects between two standard-definition video sources that can each have up to four video signals, for example, RGB with composite sync (RGBS) or RGB with sync-on-green. See Figure 1. It is also possible to select between two sets of four composite video signals with blanking and sync (CVBS). With its integrated lowpass filter (10MHz large-signal -3dB bandwidth typical), the MAX9541 can provide the anti-alias filtering before an analog-to-digital converter (ADC) or the reconstruction filtering after a digital-to-analog converter (DAC). The incoming video signals can have any DC bias because the MAX9541 has input sync-tip clamps which restore the DC level. The output amplifiers have a gain of 2V/V. The MAX9541 operates from a single 3.3V supply and consumes low quiescent power and low average power. In addition, the device also has shutdown mode. The MAX9542 is similar to the MAX9541 except that it does not have the integrated lowpass filter. As a result, the typical, large-signal bandwidth of the MAX9541 is 15MHz. Therefore, it can select between two video sources that can each have up to four video signals that are standard definition or VGA. A standard-definition signal set would be RGB with composite sync. A VGA signal set would be RGB with a 640 x 480 resolution and up to 85Hz refresh rate. See Figure 2. _______________________________________________________________________________________ 9 MAX9541/MAX9542 Pin Description MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals VDD DISPLAY PANEL MAX9541 NAVIGATION COMPUTER A/B 0.1μF IN0A COMPOSITE SYNC LPF 2V/V OUT0 75Ω 75Ω COMPOSITE SYNC CLAMPREF 0.1μF IN1A RED 75Ω CLAMPREF 0.1μF IN2A GREEN LPF 2V/V OUT1 RED 75Ω 75Ω CLAMPREF 0.1μF IN3A BLUE 75Ω CLAMPREF 0.1μF IN0B COMPOSITE SYNC LPF 2V/V OUT2 GREEN 75Ω 75Ω CLAMPREF 0.1μF IN1B RED 75Ω CLAMPREF 0.1μF IN2B GREEN LPF 2V/V OUT3 BLUE 75Ω 75Ω CLAMPREF 0.1μF BLUE VIDEO SOURCE IN3B 75Ω CLAMPREF GND Figure 1. The MAX9541 selects between two sources of RGB with composite sync, filters the signals, and drives the signals into a display panel. 10 ______________________________________________________________________________________ Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals MAX9541/MAX9542 VDD MONITOR MAX9542 PC NO. 1 A/B 0.1μF IN0A 2V/V RED OUT0 RED 75Ω 75Ω CLAMPREF 0.1μF IN1A GREEN 75Ω CLAMPREF 0.1μF IN2A BLUE 2V/V OUT1 GREEN 75Ω 75Ω CLAMPREF 0.1μF NOT USED IN3A 75Ω CLAMPREF 0.1μF IN0B RED 2V/V OUT2 BLUE 75Ω 75Ω CLAMPREF 0.1μF IN1B GREEN 75Ω CLAMPREF 0.1μF IN2B BLUE 2V/V 75Ω 75Ω PC NO. 2 OUT3 NOT USED CLAMPREF 0.1μF NOT USED IN3B 75Ω CLAMPREF GND Figure 2. The MAX9542 Selecting Between Two VGA Sources ______________________________________________________________________________________ 11 MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals Operating Modes A/B controls whether Video Input A or Video Input B is selected. See Table 1. Table 1. A/B Logic LOGIC STATE SHDN controls whether the device is on or off. See Table 2. In shutdown, the outputs are in high impedance. Input Each video source can provide up to four video signals. Every video signal must be AC-coupled to the MAX9541/MAX9542 through 0.1µF capacitors. The MAX9541/MAX9542 have sync-tip clamps and bias circuits to restore the DC level of the video signal after the input coupling capacitor. When a video input is selected, the input has a sync-tip clamp, which accepts video signals that have sync pulses or that reach their minimum level during sync. Composite video with blanking and sync (CVBS) is an example of a video signal with sync pulses. The red, green, and blue signals in an RGBS signal set are examples of signals that return to their blank level during sync. The sync-tip voltage is internally set to 300mV. When a video input is not selected, the inputs to the MAX9541/MAX9542 do not distort the video signal in case the video source is driving video signals to another video circuit such as a video multiplexer. The inputs are biased at VDD/3, which is sufficiently above ground so that the ESD diodes never forward bias as the video signal changes. The input resistance is 220kΩ, which presents negligible loading on the video current DAC. The sole exception to this condition is IN3A, in which the input circuit is always a sync-tip clamp. Table 3 summarizes which input circuit is active, dependent upon A/B. In shutdown mode (SHDN = LOW), a bias circuit is active on every input. MODE Low Video Input A High Video Input B Table 2. SHDN Logic LOGIC STATE MODE Low Off High On Multiplexer The MAX9541/MAX9542 have quadruple 2:1 multiplexers to select between either Video Input A or Video Input B as the source of the video signal. When A/B is connected to GND, Video Input A is the video source. When A/B is connected to VDD, Video Input B is the video source. Video Filter The MAX9541 filter features ±1dB passband out to 9.5MHz and 47dB attenuation at 27MHz, making the filter suitable for standard-definition video signals from all sources (e.g., broadcast and DVD). Broadcast video signals are channel limited: NTSC signals have 4.2MHz bandwidth, and PAL signals have 5MHz bandwidth. Video signals from a DVD player, however, are not channel limited; so the bandwidth of DVD video signals can approach the Nyquist limit of 6.75MHz. Recommendation: ITU-R BT.601-5 specifies 13.5MHz as the sampling rate for standard-definition video. Therefore, the maximum bandwidth of the signal is 6.75MHz. To ease the filtering requirements, most modern video systems oversample by two times, clocking the video current DAC at 27MHz. The MAX9542 does not have a filter. Table 3. Input Circuit of Input as Determined by State of A/B (SHDN = HIGH) 12 INPUT INPUT CIRCUIT A/B = LOW INPUT CIRCUIT A/B = HIGH IN0A Sync-tip clamp Bias IN1A Sync-tip clamp Bias IN2A Sync-tip clamp Bias IN3A Sync-tip clamp Sync-tip clamp IN0B Bias Sync-tip clamp IN1B Bias Sync-tip clamp IN2B Bias Sync-tip clamp IN3B Bias Sync-tip clamp ______________________________________________________________________________________ Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals MEASUREMENT POWER CONSUMPTION (mW) CONDITIONS Quiescent power consumption 69 No load. Average power consumption 175 150Ω to ground on each output. 50% flat field signal on each input. Outputs Power Consumption The video output amplifiers can both source and sink load current, allowing output loads to be DC- or AC-coupled. The amplifier output stage needs approximately 300mV of headroom from either supply rail. The devices have an internal level-shift circuit that positions the sync tip at approximately 300mV at the output. If the supply voltage is greater than 3.135V (5% below a 3.3V supply), each amplifier can drive two DC-coupled video loads to ground. If the supply is less than 3.135V, each amplifier can drive only one DC-coupled or AC-coupled video load. The quiescent power consumption and average power consumption of the MAX9541/MAX9542 are very low because of 3.3V operation and low-power circuit design. Quiescent power consumption is defined when the MAX9541/MAX9542 are operating without loads and without any video signals. Average power consumption represents the normal power consumption when the devices drive real video signals into real video loads. It is measured when the MAX9541/ MAX9542 drive 150Ω loads to ground with a 50% flat field, which serves as proxy for a real video signal. Table 4 shows the quiescent and average power consumption of the MAX9541/MAX9542. Applications Information AC-Coupling the Outputs The outputs can be AC-coupled since the output stage can source and sink current as shown in Figure 3. Coupling capacitors should be 220µF or greater to keep the highpass filter, formed by the 150Ω equivalent resistance of the video transmission line, to a corner frequency of 4.8Hz or below. The frame rate of PAL systems is 25Hz, the frame rate of NTSC systems is 30Hz, and the frame rate of VGA is usually 60Hz or higher. The corner frequency should be well below the frame rate. Power-Supply Bypassing and Ground The MAX9541/MAX9542 operate from a single-supply voltage down to 2.7V, allowing for low-power operation. Bypass VDD to GND with a 0.1µF capacitor. Place all external components as close as possible to the device. Pin Configuration Chip Information PROCESS: BiCMOS TOP VIEW + IN0A 1 16 VDD IN1A 2 15 A/B IN2A 3 IN3A 4 IN0B 5 14 OUT0 MAX9541 MAX9542 13 OUT1 12 OUT2 IN1B 6 11 OUT3 IN2B 7 10 SHDN IN3B 8 9 GND QSOP ______________________________________________________________________________________ 13 MAX9541/MAX9542 Table 4. Quiescent and Average Power Consumption MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals +3.3V 0.1μF SHDN VDD A/B 0 0.1μF MAX9541 MAX9542 BUFFER IN0A LPF* 1 75Ω 220μF 2V/V OUT0 75Ω CLAMPREF 0.1μF IN1A VIDEO SOURCE A 4 CVBS SIGNALS 75Ω 0 0.1μF BUFFER IN2A LPF* 1 2V/V 220μF OUT1 75Ω 75Ω CLAMPREF 0.1μF IN3A 75Ω 0 0.1μF BUFFER IN0B 220μF LPF* 1 2V/V OUT2 75Ω 75Ω CLAMPREF 0.1μF IN1B VIDEO SOURCE B 4 CVBS SIGNALS 75Ω 0 0.1μF BUFFER 220μF IN2B LPF* 1 75Ω 2V/V OUT3 75Ω CLAMPREF 0.1μF IN3B 75Ω GND *LOWPASS FILTER MAX9451 ONLY. Figure 3. AC-Coupled Outputs 14 ______________________________________________________________________________________ Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals +3.3V 0.1μF SHDN VDD A/B MAX9541 MAX9542 0 BUFFER 0.1μF IN0A LPF* 1 75Ω 2V/V OUT0 75Ω CLAMPREF 0.1μF IN1A 75Ω VIDEO SOURCE A 4 CVBS SIGNALS 0 0.1μF BUFFER IN2A LPF* 1 2V/V OUT1 75Ω 75Ω CLAMPREF 0.1μF IN3A 75Ω VIDEO OUTPUT 4 CVBS SIGNALS 0 0.1μF BUFFER IN0B LPF* 1 2V/V OUT2 75Ω 75Ω CLAMPREF 0.1μF IN1B VIDEO SOURCE B 4 CVBS SIGNALS 75Ω 0 0.1μF BUFFER IN2B LPF* 1 75Ω 2V/V OUT3 75Ω CLAMPREF 0.1μF IN3B 75Ω *LOWPASS FILTER MAX9451 ONLY. GND ______________________________________________________________________________________ 15 MAX9541/MAX9542 Typical Application Circuit Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. PACKAGE TYPE PACKAGE CODE DOCUMENT NO. 16 QSOP E16-4 21-0055 QSOP.EPS MAX9541/MAX9542 Quadruple, 2:1, Mux Amplifiers for Standard-Definition and VGA Signals Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.