19-1404; Rev 1; 4/99 Serially Controlled, Clickless Audio/Video Switches The MAX4571–MAX4574 serial-interface controlled switches are ideal for multimedia applications. Each device features 35Ω max on-resistance, -90dB audio off-isolation at 20kHz, -60dB video off-isolation at 1.0MHz, and “clickless” mode operation for audio applications. The MAX4571/MAX4573 contain eleven SPST switches, while the MAX4572/MAX4574 contain two SPST switches and six SPDT switches. The MAX4571/MAX4572 feature a 2-wire, I 2C™-compatible serial interface. The MAX4573/MAX4574 feature a 3-wire, SPI™/QSPI™/ MICROWIRE™-compatible serial interface. All four parts are available in 28-pin QSOP, SSOP, and wide SO packages and operate over the commercial and extended temperature ranges. Features ♦ Selectable Soft Switching Mode for “Clickless” Audio Operation ♦ 35Ω max On-Resistance ♦ -90dB Audio Off-Isolation at 20kHz -50dB Video Off-Isolation at 10MHz ♦ -90dB Audio Crosstalk at 20kHz -52dB Video Crosstalk at 10MHz ♦ Serial Interface 2-Wire, Fast-Mode, I2C-Compatible (MAX4571/72) 3-Wire, SPI/QSPI/MICROWIRE-Compatible (MAX4573/74) ♦ Single-Supply Operation from +2.7V to +5.25V Ordering Information Applications Set-Top Boxes Audio Systems PC Multimedia Boards Video Conferencing Systems Pin Configurations TOP VIEW MAX4571/MAX4573 NO1 1 28 V+ COM1 2 27 SDA (DOUT) NO2 3 26 SCL (DIN) COM2 4 25 A1 (SCLK) NO3 5 24 A0 (CS) COM3 6 23 GND NO4 7 22 NO8 COM4 8 21 COM8 NO5 9 20 NO9 COM5 10 19 COM9 NO6 11 18 NO10 COM6 12 NO7 13 COM7 14 ( ) ARE FOR MAX4573 17 COM10 16 NO11 PART TEMP. RANGE MAX4571CEI 0°C to +70°C MAX4571CAI MAX4571CWI MAX4571EEI MAX4571EAI MAX4571EWI MAX4572CEI MAX4572CAI MAX4572CWI MAX4572EEI MAX4572EAI MAX4572EWI MAX4573CEI MAX4573CAI MAX4573CWI MAX4573EEI MAX4573EAI MAX4573EWI MAX4574CEI MAX4574CAI MAX4574CWI MAX4574EEI MAX4574EAI MAX4574EWI 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -40°C to +85°C PIN-PACKAGE 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 28 QSOP 28 SSOP 28 Wide SO 15 COM11 QSOP/SSOP/SO Pin Configurations continued at end of data sheet. I2C is a trademark of Philips Corp. SPI/QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769. MAX4571–MAX4574 General Description MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches ABSOLUTE MAXIMUM RATINGS V+ to GND ................................................................-0.3V to +6V NO_ _, COM_, DOUT to GND (Note 1) ........-0.3V to (V+ + 0.3V) SCL, SDA, CS, SCLK, DIN, A0, A1 to GND..............-0.3V to +6V Continuous Current into Any Terminal..............................±10mA Peak Current (pulsed at 1ms, 10% duty cycle)................±50mA Continuous Power Dissipation (TA = +70°C) QSOP (derate 10.8mW/°C above +70°C) ...................860mW SSOP (derate 9.5mW/°C above +70°C) .....................762mW Wide SO (derate 12.5mW/°C above +70°C).............1000mW Operating Temperature Ranges MAX457_C_ _ ....................................................0°C to +70°C MAX457_E_ _..................................................-40°C to +85°C Storage Temperature Range .............................-65°C to +160°C Lead Temperature (soldering, 10sec) .............................+300°C Note 1: Signals on NO_ _ or COM_ exceeding V+ or V- are clamped by internal diodes. Limit forward-diode current to maximum current rating. 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—Single +5V Supply (V+ = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V+ V ANALOG SWITCHES Analog Signal Range (Note 3) On-Resistance VNO_ _, VCOM_ RON On-Resistance Match Between Channels (Note 4) ∆RON On-Resistance Flatness (Note 5) RFLAT NO_ _ Off-Leakage Current (Note 6) INO_ _ (OFF) COM_ Off-Leakage Current (Note 6) ICOM_ (OFF) COM _ On-Leakage Current (Note 6) ICOM_ (ON) 0 ICOM_ = 4mA, VNO_ _ = 3V, V+ = 4.75V TA = +25°C ICOM_ = 4mA, VNO_ _ = 3V, V+ = 4.75V TA = +25°C ICOM_ = 4mA; V+ = 4.75V; VNO_ _ = 1V, 2V, 3V TA = +25°C VNO_ _ = 4.5V, 1V; VCOM_ = 1V, 4.5V; V+ = 5.25V TA = +25°C -0.2 TA = TMIN to TMAX -10 VNO_ _ = 4.5V, 1V; VCOM_ = 1V, 4.5V; V+ = 5.25V TA = +25°C -0.2 TA = TMIN to TMAX -10 VCOM_ = 4.5V, 1V; VNO_ _ = 4.5V, 1V, or floating; V+ = 5.25V TA = +25°C -0.2 TA = TMIN to TMAX -10 25 TA = TMIN to TMAX 35 Ω 45 0.8 3 Ω 3 TA = TMIN to TMAX 2 TA = TMIN to TMAX 6 Ω 6 0.01 0.2 nA 10 0.01 0.2 nA 10 0.01 0.2 nA 10 AUDIO PERFORMANCE Total Harmonic Distortion plus Noise THD+N fIN = 1kHz, RL = 600Ω, VNO_ _ = 1VRMS, VNO_ _ = 2.5V 0.07 % Off-Isolation (Note 7) VISO(A) VNO_ _ = 1VRMS, fIN = 20kHz, RL = 600Ω, Figure 1 -90 dB Channel-to-Channel Crosstalk VCT(A) VNO_ _ = 1VRMS, fIN = 20kHz, RS = 600Ω, Figure 1 -90 dB 2 _______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS VIDEO PERFORMANCE Off-Isolation (Note 7) VISO(V) VNO_ _ = 1VRMS, fIN = 1.0MHz, RL = 50Ω, Figure 1 -50 dB Channel-to-Channel Crosstalk VCT(V) VNO_ _ = 1VRMS, fIN = 1.0MHz, RS = 50Ω, Figure 1 -52 dB >150 MHz 9 pF -3dB Bandwidth BW Off-Capacitance COFF(NO) RSOURCE = 50Ω, RL = 50Ω fIN = 1MHz DYNAMIC TIMING WITH CLICKLESS MODE DISABLED (Notes 8 and 12, Figure 2) Turn-On Time tONSD Turn-Off Time tOFFSD Break-Before-Make Time tBBM VNO_ _ = 1.5V, RL = 5kΩ, CL = 35pF TA = +25°C VNO_ _ = 1.5V, RL = 300Ω, CL = 35pF TA = +25°C 200 500 ns TA = TMIN to TMAX 700 75 300 ns TA = TMIN to TMAX MAX4572/MAX4574, VNO_ _ = 1.5V, TA = TMIN to TMAX 400 10 125 ns DYNAMIC TIMING WITH CLICKLESS MODE ENABLED (Note 8, Figure 2) Turn-On Time tONSE VNO_ _ = 1.5V, RL = 5kΩ, CL = 35pF, TA = +25°C 8 ms Turn-Off Time tOFFSE VNO_ _ or = 1.5V, RL = 300Ω, CL = 35pF, TA = +25°C 3 ms POWER SUPPLY Supply Voltage Range V+ TA = TMIN to TMAX +2.7 Supply Current (Note 9) I+ All logic inputs = 0 or V+, TA = TMIN to TMAX +5.25 V 6 10 µA TYP MAX UNITS V+ V ELECTRICAL CHARACTERISTICS—Single +3V Supply (V+ = 3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN ANALOG SWITCHES Analog Signal Range (Note 3) On-Resistance VNO_ _, VCOM_ RON On-Resistance Match Between Channels (Note 4) ∆RON 0 ICOM_ = 4mA, VNO_ _ =2V, V+ = 2.7V TA = +25°C ICOM_ = 4mA, VNO_ _ = 2V, V+ = 2.7V TA = +25°C 43 TA = TMIN to TMAX TA = TMIN to TMAX 90 Ω 110 1 5 Ω 5 _______________________________________________________________________________________ 3 MAX4571–MAX4574 ELECTRICAL CHARACTERISTICS—Single +5V Supply (continued) (V+ = 5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches ELECTRICAL CHARACTERISTICS—Single +3V Supply (continued) (V+ = +3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER On-Resistance Flatness (Note 5) SYMBOL RFLAT CONDITIONS ICOM_ = 4mA; V+ = 2.7V; VNO_ _ = 1V, 5V, 2V TA = +25°C MIN MAX 4 10 TA = TMIN to TMAX UNITS Ω 10 NO_ _Off-Leakage Current (Notes 6 and 10) VNO_ _ = 3V, 0.5V; VCOM_ = 0.5V, 3V; V+ = 3.6V TA = +25°C -0.2 INO_ _ (OFF) TA = TMIN to TMAX -10 COM_ Off-Leakage Current (Notes 6 and 10) VNO_ _ = 3V, 0.5V; ICOM_ (OFF) VCOM_ = 0.5V, 3V; V+ = 3.6V TA = +25°C -0.2 TA = TMIN to TMAX -10 COM _ On-Leakage Current (Notes 6 and 10) TA = +25°C -0.2 ICOM_ (ON) TA = TMIN to TMAX -10 VCOM_ = 3V, 0.5V; VNO_ _ = 3V, 0.5V, or floating; V+ = 3.6V TYP 0.01 0.2 nA 10 0.01 0.2 nA 10 0.01 0.2 nA 10 AUDIO PERFORMANCE Total Harmonic Distortion plus Noise THD+N fIN = 1kHz, RL = 600Ω, VNO_ = 0.5VRMS, VNO_ _ = 1.5V 0.07 % Off-Isolation (Note 7) VISO(A) VNO_ _ = 0.5VRMS, fIN = 20kHz, RL = 600Ω, Figure 1 -90 dB Channel-to-Channel Crosstalk VCT(A) VNO_ _ = 0.5VRMS, fIN = 20kHz, RS = 600Ω, Figure 1 -90 dB Off-Isolation (Note 7) VISO(V) VNO_ _ = 0.5VRMS, fIN = 10MHz, RL = 50Ω, Figure 1 -50 dB Channel-to-Channel Crosstalk VCT(V) VNO_ _ = 0.5VRMS, fIN = 10MHz, RS = 50Ω, Figure 1 -52 dB >150 MHz 9 pF VIDEO PERFORMANCE -3dB Bandwidth BW Off Capacitance COFF(NO) RSOURCE = 50Ω, RL = 50Ω, CL = 35pF fIN = 1MHz DYNAMIC TIMING WITH CLICKLESS MODE DISABLED (Notes 8 and 12, Figure 2) TA = +25°C Turn-On Time tONSD VNO_ _ = 1.5V, RL = 5kΩ, CL = 35pF Turn-Off Time tOFFSD TA = +25°C VNO_ _ = 1.5V, RL = 300Ω, CL = 35pF TA = TMIN to TMAX Break-Before-Make Time tBBM 300 TA = TMIN to TMAX VNO_ _ = 1.5V, TA = TMIN to TMAX 900 1000 100 300 400 10 ns ns 200 ns DYNAMIC TIMING WITH CLICKLESS MODE ENABLED (Notes 8 and 12, Figure 2) Turn-On Time tONSE VNO_ _ = 1.5V, RL = 5kΩ, CL = 35pF, TA = +25°C 8 ms Turn-Off Time tOFFSE VNO_ _ = 1.5V, RL = 300Ω, CL = 35pF, TA = +25°C 3 ms 4 _______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DIGITAL INPUTS (SCLK, DIN, CS, SCL, SDA, A0, A1) Input Low Voltage VIL Input High Voltage VIH Input Hysteresis VHYST Input Leakage Current ILEAK Input Capacitance V+ = 5V 0.8 V+ = 3V 0.6 V+ = 5V 3 V+ = 3V 2 Digital inputs = 0 or V+ -1 V 0.2 CIN V 0.01 V 1 5 µA pF DIGITAL OUTPUTS (DOUT, SDA) Output Low Voltage VOL ISINK = 6mA DOUT Output High Voltage VOH ISOURCE = 0.5mA 0.4 V+ - 0.5 V V 2-WIRE INTERFACE TIMING (Figure 3) SCL Clock Frequency fSCL DC Bus Free Time between Stop and Start Condition 400 kHz tBUF 1.3 µs START Condition Hold Time tHD:STA 0.6 µs STOP Condition Setup Time tSU:STO 0.6 Data Hold Time tHD:DAT 0 Data Setup Time tSU:DAT 100 ns Clock Low Period tLOW 1.3 µs Clock High Period tHIGH 0.6 µs µs 0.9 µs SCL/SDA Rise Time tR (Note 11) 20 + 0.1Cb 300 ns SCL/SDA Fall Time tF (Note 11) 20 + 0.1Cb 300 ns fOP DC 2.1 MHz DIN to SCLK Setup tDS 100 DIN to SCLK Hold tDH SCLK Fall to Output Data Valid tDO 3-WIRE TIMING (Figure 5) Operating Frequency CLOAD = 50pF 20 ns 0 ns 200 ns CS to SCLK Rise Setup tCSS 100 ns CS to SCLK Rise Hold tCSH 0 ns CS High Pulse Width tCSW 200 ns SCLK Pulse Width Low tCL 200 ns SCLK Pulse Width High tCH 200 ns Rise Time (SCLK, DIN, CS) tR 2 µs Fall Time (SCLK, DIN, CS) tF 2 µs _______________________________________________________________________________________ 5 MAX4571–MAX4574 I/O INTERFACE CHARACTERISTICS (V+ = +2.7V to +5.25V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) The algebraic convention is used in this data sheet; the most negative value is shown in the minimum column. Guaranteed by design. Not subject to production testing. ∆RON = RON(MAX) - RON(MIN). Resistance flatness is defined as the difference between the maximum and minimum on-resistance values, as measured over the specified analog signal range. Note 6: Leakage parameters are 100% tested at maximum rated temperature, and guaranteed by correlation at TA = +25°C. Note 7: Off-isolation = 20 log [VCOM_ / VNO_ _ ], VCOM_ = output, VNO_ _ = input to off switch. Note 8: All timing is measured from the rising clock edge of the ACK bit for 2-wire, and from the rising edge of CS for 3-wire. Turnoff time is defined at the output of the switch for a 0.5V change, tested with a 300Ω load to ground. Turn-on time is measured with a 5kΩ load resistor to GND. All timing is shown with respect to 20% V+ and 70% V+, unless otherwise noted. Note 9: Supply current can be as high as 2mA per switch during switch transitions in the clickless mode, corresponding to a 28mA total supply transient current requirement. Note 10: Leakage testing for single-supply operation is guaranteed by testing with a single +5.25V supply. Note 11: Cb = capacitance of one bus line in pF. Tested with Cb = 400pF. Note 12: Typical values are for MAX4573/MAX4574 devices. Note 2: Note 3: Note 4: Note 5: Typical Operating Characteristics (V+ = +5V, TA = +25°C, unless otherwise noted.) ON-RESISTANCE vs. VCOM AND TEMPERATURE 30 35 V+ = 3.3V 30 TA = +70°C 26 TA = +25°C 24 10 CURRENT (nA) 40 TA = +85°C 28 100 MAX4571-4 toc02 V+ = 2.7V ON-RESISTANCE (Ω) 1 COM_ OFF 0.1 NO_ _ OFF 22 0.01 25 TA = -40°C 20 V+ = 5.0V NO_ _ ON 18 20 0 1 2 3 4 0.001 0 5 1 2 3 4 5 -40 -20 0 20 40 60 VCOM (V) VCOM (V) TEMPERATURE (°C) SUPPLY CURRENT vs. TEMPERATURE CHARGE INJECTION vs. VCOM ON/OFF TIME vs. TEMPERATURE (HARD MODE) 5.0 2 4.9 600 500 TIME (ns) Q (pC) 4.7 tON, V+ = 3V 400 1 4.8 0 80 MAX4571-4 toc06 3 MAX4571-4 toc04 5.1 MAX4571-4 toc05 ON-RESISTANCE (Ω) 45 LEAKAGE CURRENT vs. TEMPERATURE 32 MAX4571-4 toc01 50 MAX4571-4 toc03 ON-RESISTANCE vs. VCOM CURRENT (µA) MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches tON, V+ = 5V 300 200 -1 tOFF, V+ = 3V 4.6 -2 100 4.5 -3 0 tOFF, V+ = 5V -40 -20 0 20 40 TEMPERATURE (°C) 6 60 80 0 1 2 3 VCOM (V) 4 5 -40 -20 0 20 40 TEMPERATURE (°C) _______________________________________________________________________________________ 60 80 Serially Controlled, Clickless Audio/Video Switches VIDEO FREQUENCY RESPONSE AUDIO FREQUENCY RESPONSE 600Ω IN AND OUT -20 0 MAX4571-4 toc08 0 MAX4571-4 toc07 600Ω IN AND OUT SIGNAL = 1VRMS INSERTION-LOSS -20 0.1 LOSS (dB) LOSS (dB) -40 -60 OFF-ISOLATION -40 CROSSTALK -60 -80 CROSSTALK -80 -100 0.01 1000 10,000 100,000 10 FREQUENCY (Hz) 100 1000 10,000 0.1 100,000 10 100 ON/OFF TIMES (HARD MODE) MAX4571-4 toc10 CS 5V/div 1 FREQUENCY (MHz) FREQUENCY (Hz) ON/OFF TIMES (SOFT MODE) CS 5V/div tON tON 1V/div 1V/div tOFF 1V/div tOFF TIME (2ms/div) TIME (50ns/div) SOFT MODE RISE TIME SOFT MODE FALL TIME MAX4571-4 toc12 1V/div 50Ω IN AND OUT -100 -120 MAX4571-4 toc13 100 OFF-ISOLATION AMPLITUDE (500mV/div) MAX4571-4 toc11 10 AMPLITUDE (500mV/div) THD + N (%) 1 MAX4571-4 toc09 TOTAL HARMONIC DISTORTION + NOISE vs. FREQUENCY TIME (500µs/div) TIME (500µs/div) _______________________________________________________________________________________ 7 MAX4571–MAX4574 Typical Operating Characteristics (continued) (V+ = 5V,TA = +25°C, unless otherwise noted.) MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches Pin Descriptions PIN NAME FUNCTION MAX4571 MAX4572 MAX4571 MAX4572 1, 3, 5, 7, 9, 11, 13, 22, 20, 18, 16 – NO1–NO11 – Normally Open Terminals – 1, 4, 7, 10 – NO1A–NO4A Normally Open Terminals – 3, 6, 9, 12 – NO1B–NO4B Normally Open Terminals – 13, 16 – NO5, NO8 Normally Open Terminals – 22, 19, 20, 17 – NO6A, NO7A, NO6B, NO7B Normally Open Terminals 2, 4, 6, 8, 10, 12, 14, 21, 19, 17, 15 2, 5, 8, 11, 14, 21, 18, 15 COM1–COM11 COM1–COM8 Common Terminals 23 23 GND GND 24 24 A0 A0 LSB + 1 of 2-Wire Serial Interface Address Field 25 25 A1 A1 LSB + 2 of 2-Wire Serial Interface Address Field 26 26 SCL SCL Clock Input of 2-Wire Serial Interface 27 27 SDA SDA Data Input of 2-Wire Serial Interface 28 28 V+ V+ MAX4573 MAX4574 MAX4573 MAX4574 1, 3, 5, 7, 9, 11, 13, 22, 20, 18, 16 – NO1–NO11 – Normally Open Terminals – 1, 4, 7, 10 – NO1A–NO4A Normally Open Terminals – 3, 6, 9, 12 – NO1B–NO4B Normally Open Terminals – 13, 16 – NO5, NO8 Normally Open Terminals – 22, 19, 20, 17 – NO6A, NO7A, NO6B, NO7B Normally Open Terminals 2, 4, 6, 8, 10, 12, 14, 21, 19, 17, 15 2, 5, 8, 11, 14, 21, 18, 15 COM1–COM11 COM1–COM8 Common Terminals 23 23 GND GND 24 24 CS CS Chip Select of 3-Wire Serial Interface 25 25 SCLK SCLK Clock Input of 3-Wire Serial Interface 26 26 DIN DIN Clock Input of 3-Wire Serial Interface 27 27 DOUT DOUT Data Output of 3-Wire Serial Interface 28 28 V+ V+ PIN 8 Ground Positive Supply Voltage NAME FUNCTION Ground Positive Supply Voltage _______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches MAX4571 MAX4572 MAX4573 MAX4574 V+ 10nF 2/3 RL RL SIGNAL GENERATOR 0dBm NO_ _ 2/3 DECODER/ CONTROLLER COM2 NO2 GND 50Ω NO1 COM1 ANALYZER DECODER/ CONTROLLER SIGNAL GENERATOR 0dBm MAX4571 MAX4572 MAX4573 MAX4574 V+ COM_V+ ANALYZER V+ MAX4571–MAX4574 10nF N.C. GND a) Off-Isolation b) Crosstalk Figure 1. Off-Isolation and Crosstalk 3V SCL MAX4571 MAX4572 MAX4573 MAX4574 0 VOUT 0 V+ µP 0.9 • VOUT 2-Wire V+ NO NO_ _ 2 OR 3 ACKNOWLEDGE BIT tr < 20ns 50% tf < 20ns tON VOUT COM_ VOUT RL 300Ω 0 0.1 • VOUT tOFF CL 35pF 3V DECODER/ CONTROLLER CS 50% 0 SERIAL INTERFACE VOUT 0.9 • VOUT GND 3-Wire 0 tON CL INCLUDES FIXTURE AND STRAY CAPACITANCE VOUT = VCOM [RL / (RL + RON)] VOUT 0 0.1 • VOUT tOFF Figure 2. Switching Time _______________________________________________________________________________________ 9 MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches Detailed Description The MAX4571–MAX4574 are serial-interface controlled switches with soft-mode “clickless” and hard-mode operating capability. The MAX4571/MAX4573 contain 11 SPST switches, while the MAX4572/MAX4574 contain two SPST switches and six SPDT switches. The SPDT switches are actually 2-to-1 multiplexers, in that each SPDT is really two independent SPST switches with a common node, as shown in the Pin Configurations. Each switch is controlled independently by either the SPI or I2C interface. Audio off-isolation is -90dB at 20kHz, crosstalk is at least -90dB at 20kHz, and video off-isolation is at least -50dB at 10MHz. Each switch of any device may be set to operate in either soft or hard mode. In soft mode, the switching transition is slowed to avoid the audible “clicking” that can occur when switches are used to route audio signals. In hard mode, the switches are not slowed down, making this mode useful when a faster response is required. If a new command is issued while any softmode switch is transitioning, the switch transition time is decreased so it reaches its final state before the new command is executed. Soft mode is the power-up default state for all switches. Switches in the same mode are guaranteed to be break-before-make relative to each other. Break-before-make does not apply between switches operating in different modes. These devices operate from a single supply of +2.7V to +5.25V. The MAX4571/MAX4572 feature a 2-wire, I2Ccompatible serial interface, and the MAX4573/ MAX4574 feature a 3-wire, SPI/QSPI/MICROWIRE-compatible serial interface. Applications Information Switch Control The MAX4571–MAX4574 have a common command and control-bit structure, the differences being only in the interface type (2-wire or 3-wire) and in the switch configurations. The SWITCHSET command controls the open/closed states of the various switches. MODESET controls soft/hard-mode states of the switches. There are also NO_OP and RESET commands. The NO_OP command is useful for daisy-chaining multiple 3-wire parts. The RESET command places a device in a state identical to its power-up state, with all switches open and in soft switching mode. Table 1 shows the configuration of the command bits and their related commands. Table 2 shows the config- uration of the data bits and their related switches. The arrangement of the command bits and the data bits depends on the interface type (2-wire or 3-wire). After a SWITCHSET command is issued, a logic 1 in any databit location closes the associated switch, while a logic 0 opens it. After a MODESET command, a logic 1 in any data-bit location sets the associated switch into hard mode, while a logic 0 sets it into soft mode. 2-Wire Serial Interface The MAX4571/MAX4572 use a 2-wire, I2C-compatible serial interface requiring only two I/O lines of a standard microprocessor port for communication. These devices use the SendByte™ and WriteWord™ protocols. The SendByte protocol is used only for the RESET command. The WriteWord protocol is used for the MODESET and SWITCHSET commands. The first byte of any 2-wire serial-interface transaction is always the address byte. To address a given chip, the A0 and A1 bits in the address byte (Table 3) must duplicate the values present at the A0 and A1 pins of that chip, and the rest of the address bits must be configured as shown in Table 3. Connect the A0 and A1 pins to V+ or to GND, or drive them with CMOS logic levels. The second byte is the command byte. The possible commands are RESET, MODESET, and SWITCHSET. RESET sets all switches to the initial power-up state (open and in soft switching mode). The RESET command is executed on the rising clock edge of the acknowledge bit after the command byte. The MODESET and SWITCHSET commands are each followed by two data bytes. The first data byte is buffered so all the data latches switch together. MODESET and SWITCHSET are executed on the rising clock edge of the acknowledge bit after the second data byte. Table 3 details the 2-wire interface data structure. Figures 3 and 4 and the I/O Interface Characteristics detail the timing of the 2-wire serial-interface protocol. All bytes of the transmission, whether address, command, or data, are sent MSB first. The MAX4571/MAX4572 are receive-only devices and must be controlled by a bus master device. A bus master signals the beginning of a transmission with a start condition by transitioning SDA from high to low while SCL is high. The slave devices monitor the serial bus continuously, waiting for a start condition followed by an address byte. When a device recognizes its address byte, it acknowledges by pulling the SDA line low for one clock period; it is then ready to accept command and data bytes. The device then issues a similar acknowledgment after the command byte, and again after each data byte. When the master has finished SendByte and WriteWord are trademarks of Philips Corp. 10 ______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches MSB MSB - 1 COMMAND 0 0 RESET 0 1 MODESET 1 0 NO_OP 1 1 SWITCHSET MAX4571–MAX4574 Table 1. Command Bit Mapping DESCRIPTION Sets all switches open and in soft switching mode. Sets specified switches to soft or hard mode. No Operation. Sets specified switches open or closed. Table 2. Data-Bit Switch Control DATA BIT MAX4571/MAX4573 MAX4572/MAX4574 SWITCH SWITCH TERMINALS SWITCH SWITCH TERMINALS D13 X X SW8 15, 16 D12 X X SW5 13, 14 D11 X X SW7B 17, 18 D10 SW11 15, 16 SW7A 18, 19 D9 SW10 17, 18 SW6B 20, 21 D8 SW9 19, 20 SW6A 21, 22 D7 SW8 21, 22 SW4B 11, 12 D6 SW7 13, 14 SW4A 10, 11 D5 SW6 11, 12 SW3B 8, 9 D4 SW5 9, 10 SW3A 7, 8 D3 SW4 7, 8 SW2B 5, 6 D2 SW3 5, 6 SW2A 4, 5 D1 SW2 3, 4 SW1B 2, 3 D0 (LSB) SW1 1, 2 SW1A 1, 2 X = Don’t care communicating with the slave, it issues a stop condition by transitioning SDA from low to high while SCL is high. The bus is then free for another transmission. 3-Wire Serial Interface The MAX4573/MAX4574 use a 3-wire SPI/QSPI/ MICROWIRE-compatible serial interface. An active-low chip-select pin, CS, enables the device to receive data from the serial input pin, DIN. Command and data information are clocked in on the rising edge of the serialclock signal (SCLK) MSB first. A total of 16 bits are needed in each write cycle. The write cycle allows two 8-bit-wide transfers if CS remains low for the entire 16 bits. The command code is contained in the two MSBs of the 16-bit word. The remaining bits control the switches as shown in Table 4. While shifting in the serial data, the device remains in its original configuration. A rising edge on CS latches the data into the MAX4573/MAX4574 internal registers, initiating the device’s change of state. Table 4 shows the details of the 3-wire interface data structure. Figures 5 and 6 and the I/O Interface Characteristics show the timing details of the 3-wire interface. If the two command bits initiate a SWITCHSET command, a logic 1 in a switch control location closes the associated switch, while a logic 0 opens it. If the command bits initiate a MODESET command, a logic 1 in a switch control location sets the associated switch into hard mode, while a logic 0 sets it into soft, “clickless” mode. For command-bit configurations, see Table 1. Using Multiple Devices There are two ways to connect multiple devices to the same 3-wire serial interface. The first involves using the DOUT pin. DOUT presents a copy of the last bit of the internal shift register, useful for daisy-chaining multiple devices. Data at DOUT are simply the input data delayed by 16 clock cycles, appearing synchronous with SCLK’s falling edge. After CS goes high, DOUT holds the last bit in the shift register until new data are shifted into DIN. For a simple interface using several MAX4573/MAX4574 devices, daisy-chain the shift reg- ______________________________________________________________________________________ 11 MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches Table 3. 2-Wire Serial-Interface Data Format RESET Command Address Byte Command Byte (RESET) MSB S R T 0 LSB 1 1 0 1 A 1 A 0 0 MSB A C K LSB 0 0 X X X X X X A C K S T P SWITCHSET Command Command Byte (SWITCHSET) Address Byte LSB MSB S R T 0 1 1 0 1 A 1 A 0 0 MSB A C K 1 LSB 1 X X X X X X A C K MAX4571 Second Data Byte First Data Byte LSB MSB X X X X X SW 11 SW 10 LSB MSB SW 9 A C K SW 8 SW 7 SW 6 SW 5 SW 4 SW 3 SW 2 SW 1 SW 1B SW 1A A C K S T P A C K S T P A C S T K P MAX4572 Second Data Byte First Data Byte LSB MSB X X SW 8 SW 5 SW 7B SW 7A SW 6B LSB MSB SW 6A A C K SW 4B SW 4A SW 3B SW 3A SW 2B SW 2A MODESET Command Command Byte (MODESET) Address Byte MSB MSB S R T 0 1 1 0 1 A 1 A 0 0 A C K 0 LSB 1 X X X X X X A C K MAX4571 Second Data Byte First Data Byte LSB MSB X X X X X SW 11 SW 10 SW 9 LSB MSB A C SW 8 SW 7 SW 6 SW 5 SW 4 SW 3 SW 2 SW 1 K MAX4572 First Data Byte Second Data Byte LSB MSB X X SW SW SW SW SW SW A SW SW SW SW SW SW SW SW A S 8 5 7B 7A 6B 6A C K 4B 4A 3B 3A 2B 2A 1B 1A C K T P X = Don't Care SRT = Start Condition ACK = Acknowledge Condition 12 LSB MSB STP = Stop Condition Logic "0" in any data bit location places the associated switch open or in soft (clickless) switching mode. Logic "1" in any data bit location places the associated switch closed or in hard switching mode. For command bit configuration see Table 1. ______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches MAX4573 (11 SPST) MSB LSB COMMAND SWITCH CONTROL D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 C1 C0 X X X SW11 SW10 SW9 SW8 SW7 SW6 SW5 SW4 SW3 SW2 SW1 MAX4574 (6 SPDT + 2 SPST) MSB LSB COMMAND SWITCH CONTROL D15 D14 D13 D12 D11 C1 C0 SW8 SW5 SW7B 70% SDA D10 D9 D8 SW7A SW6B SW6A D7 70% 20% D6 SW4B SW4A D5 D4 D3 SW3B SW3A D2 70% 20% 70% 20% tSU, DAT D1 D0 SW2B SW2A SW1B SW1A 70% 20% 20% tBUF tSU, STA tHD, STA tLOW 70% 20% SCL tSU, STO tHD, DAT 70% 20% tHIGH tHD, STA tR 70% 20% 70% 70% 70% tF START CONDITION REPEATED START CONDITION STOP CONDITION START CONDITION Figure 3. 2-Wire Serial-Interface Timing Diagram COMMAND BYTE ADDRESS BYTE SECOND DATA BYTE FIRST DATA BYTE SDA MSB LSB ACK MSB LSB ACK MSB LSB ACK MSB LSB ACK SCL STOP CONDITION START CONDITION Figure 4. A Complete 2-Wire Serial-Interface Transmission ______________________________________________________________________________________ 13 MAX4571–MAX4574 Table 4. 3-Wire Serial-Interface Data Format MAX4571–MAX4574 Serially Controlled, Clickless Audio/Video Switches isters by connecting DOUT of the first device to DIN of the second, etc. Connect the CS pins of all devices together. Data are shifted through the MAX4573/ MAX4574s in series. When CS is brought high, all devices are updated simultaneously. If any of the devices in the chain are to be left unchanged, use a NO_OP command for that device, as shown in Table 1. An alternate way of connecting multiple devices is to decode the CS line. In this case the DOUT pin is not used and the DIN pins of all devices are connected together. Address decode logic individually controls the CS line of each device. When a device is to be selected its CS line is brought low, data are shifted in, and its CS is then brought high to execute the command. 20% CS 20% 70% tCSW tCSH SCLK 20% tDH 20% tCSO tCH tCL tCSS 70% 20% 20% 70% 70% 20% tDS D15 DIN D14 D1 D0 tDO DOUT Figure 5. 3-Wire Serial-Interface Timing Diagram CS COMMAND EXECUTED SCLK 1 8 16 9 DIN D15 D14 D13.... MSB D2 D1 D0.... LSB DOUT Q15........ MSB FROM PREVIOUS WRITE .........00 LSB FROM PREVIOUS WRITE Figure 6. A Complete 3-Wire Serial-Interface Transmission 14 ______________________________________________________________________________________ Serially Controlled, Clickless Audio/Video Switches ___________________Chip Information TRANSISTOR COUNT: 5397 TOP VIEW MAX4572/MAX4574 NO1A 1 28 V+ COM1 2 27 SDA (DOUT) NO1B 3 26 SCL (DIN) NO2A 4 25 A1 (SCLK) COM2 5 24 A0 (CS) NO2B 6 23 GND NO3A 7 22 NO6A COM3 8 21 COM6 NO3B 9 20 NO6B NO4A 10 19 NO7A COM4 11 18 COM7 NO4B 12 17 NO7B NO5 13 16 NO8 COM5 14 15 COM8 QSOP/SSOP/SO ( ) ARE FOR MAX4574 QSOP.EPS Package Information ______________________________________________________________________________________ 15 MAX4571–MAX4574 Pin Configurations (continued) Serially Controlled, Clickless Audio/Video Switches SOICW.EPS SSOP.EPS MAX4571–MAX4574 Package Information (continued) 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 © 1999 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.