19-5541; Rev 1; 3/11 Octal High-Voltage Transmit/Receive Switches Features The MAX4936–MAX4939 are octal, high-voltage, transmit/ receive (T/R) switches. The T/R switches are based on a diode bridge topology, and the amount of current in the diode bridges can be programmed through an SPIK interface. All devices feature a latch-clear input to asynchronously turn off all T/R switches and put the device into a low-power shutdown mode. The MAX4936/ MAX4938 include the T/R switch and grass-clipping diodes, performing both transmit and receive operations. The MAX4937/MAX4939 include just the T/R switch and perform the receive operation only. S Low Power: Low Impedance (5ω) with 1.5mA Bias The MAX4936/MAX4938 transmit path is low impedance during high-voltage transmit and high impedance during low-voltage receive, providing isolation between transmit and receive circuitry. The high-voltage transmit path is high bandwidth, low distortion, and low jitter. The receive path for all devices is low impedance during low-voltage receive and high impedance during high-voltage transmit, providing protection to the receive circuitry. The low-voltage receive path is high bandwidth, low noise, low distortion, and low jitter. Each T/R switch can be individually programmed on or off, allowing these devices to also be used as receive path multiplexers. The MAX4936/MAX4937 feature clamping diodes to protect the receiver input from voltage spikes due to leakage currents flowing through the T/R switches during transmission. The MAX4938/MAX4939 do not have clamping diodes and rely on clamping diodes integrated in the receiver front end. Current Only S Low Noise < 0.5nV/√Hz (typ) with 1.5mA Bias Current Only S Wide -3dB Bandwidth 65MHz (typ) S Easy Programming with SPI Interface S High Density (8 Channels per Package) S Grass-Clipping Diodes with Low-Voltage Isolation (MAX4936/MAX4938) S Output Clamp Diodes for Receiver Protection (MAX4936/MAX4937) S Global Shutdown Control (CLR) S Each T/R Switch Can Be Individually Programmed On or Off S Low-Voltage Receive Path with High-Voltage Protection S Space-Saving, 5mm x 11mm, 56-Pin TQFN Package Applications Medical/Industrial Imaging Ultrasound High-Voltage Transmit and Low-Voltage Isolation All devices are available in a small, 56-pin, 5mm x 11mm TQFN package, and are specified over the commercial 0NC to +70NC temperature range. Ordering Information/Selector Guide LOW-VOLTAGE ISOLATION HIGH-VOLTAGE PROTECTION OUTPUT CLAMP TEMP RANGE MAX4936CTN+ Yes Yes Yes 0NC to +70NC 56 TQFN-EP* MAX4937CTN+ No Yes Yes 0NC to +70NC 56 TQFN-EP* MAX4938CTN+** Yes Yes No 0NC to +70NC 56 TQFN-EP* MAX4939CTN+** No Yes No 0NC to +70NC 56 TQFN-EP* PART PIN-PACKAGE +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. **Future product—contact factory for availability. SPI is a trademark of Motorola, Inc. ________________________________________________________________ Maxim Integrated Products 1 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. MAX4936–MAX4939 General Description MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND, unless otherwise noted.) VDD Positive Supply Voltage....................................-0.3V to +6V VCC, LVCC_ Positive Supply Voltage .....................-0.3V to +6V VEE, LVEE_ Negative Supply Voltage . ...................-6V to +0.3V CLK, DIN, CLR, LE Input Voltage ...........................-0.3V to +6V DOUT Output Voltage ...............................-0.3V to (VDD + 0.3V) HV_ Input Voltage (MAX4936/MAX4938) ..........-120V to +120V COM_ Input/Output Voltage................................-120V to +120V NO_ Output Voltage (MAX4936/MAX4937)....................... Q1.5V NO_ Output Voltage (MAX4938/MAX4939).......................... Q6V Voltage Difference Across Any or All HV_ (MAX4936/MAX4938) . ..................................... Q230V Voltage Difference Across Any or All COM_ ................... Q230V Continuous Current (HV_ to COM_ ) (MAX4936/MAX4938)...Q250mA Continuous Current (Any Other Terminal)...................... Q100mA Peak Current (HV_ to COM_ ) (MAX4936/MAX4938) (Pulsed at 1ms, 0.1% Duty Cycle) . ............................... Q2.5A Continuous Power Dissipation (TA = +70NC) TQFN (derate 41.0mW/NC above +70NC) ..................3279mW Operating Temperature Range.............................. 0NC to +70NC Storage Temperature Range............................. -65NC to +150NC Junction Temperature.................................................... +150NC Lead Temperature (soldering, 10s).................................+300NC Soldering Temperature (reflow).......................................+260NC 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. PACKAGE THERMAL CHARACTERISTICS (Note 1) TQFN Junction-to-Ambient Thermal Resistance (qJA)............44°C/W Junction-to-Case Thermal Resistance (qJC)..................10°C/W Note 1: P ackage thermal resistance were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VDD = +1.62V to +5.5V, VCC = +2.7V to +5.5V, VEE = -2.7V to -5.5V, VCLR = 0V, LVCC_ = VCC, LVEE_ = VEE, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS +115 V 220 V VHV_ +1 V +115 V 220 V STATIC CHARACTERISTICS HV_ Input Voltage Range VIRHV_ |Difference Across Any or All HV_ | MAX4936/MAX4938 only -115 MAX4936/MAX4938 only COM_ Output Voltage Range VORCM_ COM_ Input Voltage Range VIRCM_ |VHV_| R +2V, IHV_ = Q100mA (MAX4936/ MAX4938 only) VHV_ -1 VHV_ Q 0.85 -115 |Difference Across Any or All COM_ | NO_ Output Voltage Range VORNO_ VCC = +5V, VEE = -5V, |VCOM_| R +2V, RL = 200I, CL = 30pF, ICH_ = 10mA (MAX4936/MAX4937 only) VCC = +5V, VEE = -5V, |VCOM_| < +0.4V, RL = 200I, CL = 30pF, ICH_ = 1.5mA HV_ to COM_ Continuous Current ICN_ VCOM_ = 0V (MAX4936/MAX4938 only) HV_ to COM_ Drop VCN_ VCOM_ = 0V, ICN_ = Q2A (MAX4936/MAX4938 only) Diode Bridge Voltage Offset VOFF_ VCC = +5V, VEE = -5V, COM_ = unconnected, NO_ = unconnected, ICH = 1.5mA -1 Q0.75 +1 V VCOM_ - 0.2 VCOM_ Q 0.1 -200 VCOM_ + 0.2 +200 V Q2 -200 2 _______________________________________________________________________________________ mA +200 mV Octal High-Voltage Transmit/Receive Switches (VDD = +1.62V to +5.5V, VCC = +2.7V to +5.5V, VEE = -2.7V to -5.5V, VCLR = 0V, LVCC_ = VCC, LVEE_ = VEE, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2) PARAMETER HV_ Off-Leakage Current COM_ Off-Leakage Current NO_ Off-Leakage Current SYMBOL ILHV_ ILCOM_ ILNO_ CONDITIONS MIN TYP MAX UNITS |VHV_ - VCOM_ | < +0.3V, VCOM_ = 0V (MAX4936/MAX4938 only) -3 +3 FA |VHV_ - VCOM_ | < +0.3V, VHV_ = 0V, switch is off (MAX4936/MAX4938 only) -3 +3 FA HV_ = unconnected, switch is off (MAX4936/MAX4938 only) -1 +1 FA Switch is off (MAX4937/MAX4939 only) -1 +1 FA MAX4936/MAX4937 -2 +2 MAX4938/MAX4939 -1 +1 |VNO_| < +0.3V, switch is off FA DYNAMIC CHARACTERISTICS Diode Bridge Turn-On Time tON VCC = +5V, VEE = -5V, RL = 200I, ICH = 1.5mA, CL = 30pF, VCOM_ = Q0.4V, Figure 1 200 ns Diode Bridge Turn-Off Time tOFF VCC = +5V, VEE = -5V, RL = 200I, ICH = 1.5mA, CL = 30pF, VCOM_ = Q0.4V, Figure 1 5 ms Reverse Recovery Time tRR IFWD = IRVR = 10mA SPI Power-Up Delay tDLY Small-Signal COM_ to NO_ On Impedance -3dB Bandwidth Off-Isolation Crosstalk RICOM_ BW VISO VCT 450 ns 500 Fs VCC = +5V, VEE = -5V, VNO_ = 0V, ICH = 1.5mA, f = 5MHz 4.5 I COM_ to NO_, switch is on, |VCOM_| < +0.4V, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA 65 MHz HV_ to COM_, |VHV_ - VCOM_ | < +0.3V, VCC = +5V, VEE = -5V, RL = 100I, CL = 100pF, f = 1MHz (MAX4936/MAX4938 only) -50 COM_ to NO_, switch is off, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, f = 1MHz -75 Between any two HV_ to COM_ channels, |VHV_| R +2V, VCC = +5V, VEE = -5V, RL = 100I, CL = 100pF, f = 5MHz (MAX4936/MAX4938 only) -60 Between any two COM_ to NO_ channels, switch is on, |VCOM_| < +0.4V, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA, f = 5MHz -71 dB dB _______________________________________________________________________________________ 3 MAX4936–MAX4939 ELECTRICAL CHARACTERISTICS (continued) MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches ELECTRICAL CHARACTERISTICS (continued) (VDD = +1.62V to +5.5V, VCC = +2.7V to +5.5V, VEE = -2.7V to -5.5V, VCLR = 0V, LVCC_ = VCC, LVEE_ = VEE, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2) PARAMETER SYMBOL 2nd Harmonic Distortion HD2 3rd Harmonic Distortion HD3 Two-Tone Intermodulation Distortion (Note 3) HV_ Off Capacitance COM_ Off Capacitance IMD3 CHV_(OFF) CCOM_(OFF) CONDITIONS MIN TYP MAX UNITS HV_ to COM_, |VCOM_| R +2V, VCC = +5V, VEE = -5V, RL = 100I, CL = 100pF, f = 5MHz (MAX4936/MAX4938 only) -90 COM_ to NO_, switch is on, |VCOM_| < +0.4V, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA, f = 5MHz -95 HV_ to COM_, |VCOM_| R +2V, VCC = +5V, VEE = -5V, RL = 100I, CL = 100pF, f = 5MHz (MAX4936/MAX4938 only) -90 COM_ to NO_, switch is on, |VCOM_| < +0.4V, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA, f = 5MHz -115 COM_ to NO_, switch is on, |VCOM_| < +0.4V, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA, f1 = 5MHz, f2 = 5.01MHz -77 dBc |VHV_ - VCOM_ | < +0.3V (MAX4936/MAX4938 only) 12 pF |VHV_ - VCOM_ | < +0.3V, switch is off (MAX4936/MAX4938 only) 17 Switch is off (MAX4937/MAX4939 only) 12 dBc dBc pF NO_ On Capacitance CNO_(ON) |VNO_| < +0.4V, switch is on 20 pF NO_ Off Capacitance CNO_(OFF) |VNO_| < +0.4V, switch is off 7.5 pF DIGITAL I/Os (CLR, DIN, DOUT, CLK, LE) Input High Voltage Input Low Voltage Input Hysteresis VIH VIL VHYST VDD = +2.25V to +5.5V VDD 0.5 VDD = +1.62V to +1.98V 1.4 V VDD = +2.25V to +5.5V 0.6 VDD = +1.62V to +1.98V 0.4 VDD = +3V 50 VDD = +1.8V 90 Input Leakage Current IIL Input Capacitance CIN DOUT Low Voltage VOL ISINK = 5mA DOUT High Voltage VOH ISOURCE = 5mA CLR, DIN, CLK, LE = GND or VDD -1 V mV +1 5 FA pF 0.4 VDD 0.4 V V POWER SUPPLY (VDD, VCC, VEE) Positive Logic Supply Voltage VDD +1.62 +5.5 V Positive Analog Supply Voltage VCC +2.7 +5.5 V Negative Analog Supply Voltage VEE -5.5 -2.7 V 4 _______________________________________________________________________________________ Octal High-Voltage Transmit/Receive Switches (VDD = +1.62V to +5.5V, VCC = +2.7V to +5.5V, VEE = -2.7V to -5.5V, VCLR = 0V, LVCC_ = VCC, LVEE_ = VEE, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS Positive Logic Supply Current IDD CLR, DIN, CLK, LE = GND or VDD Positive Analog Supply Current ICC Per channel, switch is on, VCC = +5V, VEE = -5V, ICH = 1.5mA Positive Analog Shutdown Supply Current Negative Analog Supply Current ICC_SHDN IEE MIN +1.15 TYP +1.5 CLR = high Per channel, switch is on, VCC = +5V, VEE = -5V, ICH = 1.5mA -2 -1 -1.5 MAX UNITS +1 FA +2 mA +1 FA -1.15 mA Negative Analog Shutdown Supply Current IEE_SHDN CLR = high On Power-Supply Rejection Ratio PSRRON VCC to NO_ or VEE to NO_, switch is on, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, ICH = 1.5mA, f = 1MHz -77 dB Off Power-Supply Rejection Ratio PSRROFF VCC to NO_ or VEE to NO_, switch is off, VCC = +5V, VEE = -5V, RL = 200I, CL = 30pF, f = 1MHz -80 dB LOGIC TIMING (CLR, DIN, DOUT, CLK, LE) (Figure 1) VDD = 3V Q10% CLK Period tCP VDD = 1.8V Q10% CLK High Time tCH CLK Low Time tCL CLK to DOUT Delay tDO DIN to CLK Setup Time tDS DIN to CLK Hold Time tDH CLK to LE Setup Time tCS LE Low Pulse Width tWL CLR High Pulse Width tWC FA 50 ns 100 VDD = 3V Q10% 20 VDD = 1.8V Q10% 45 VDD = 3V Q10% 20 VDD = 1.8V Q10% 45 VDD = 3V Q10%, CL P 20pF 3 30 VDD = 1.8V Q10%, CL P 20pF 7 70 VDD = 3V Q10% 10 VDD = 1.8V Q10% 16 VDD = 3V Q10% 4 VDD = 1.8V Q10% 4 VDD = 3V Q10% 36 VDD = 1.8V Q10% 65 VDD = 3V Q10% 14 VDD = 1.8V Q10% 22 VDD = 3V Q10% 20 VDD = 1.8V Q10% 40 ns ns ns ns ns ns ns ns Note 2: A ll specifications are 100% production tested at TA = +70NC, unless otherwise noted. Specifications at 0NC are guaranteed by design. Note 3: See the Ultrasound-Specific IMD3 Specification section. _______________________________________________________________________________________ 5 MAX4936–MAX4939 ELECTRICAL CHARACTERISTICS (continued) MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches DN + 1 DIN DN 50% 50% 50% LE DN - 1 50% tWL tCS 50% 50% CLK tDS tDH tDO 50% DOUT tOFF OFF T/R SWITCH 10% ON CLR tON 90% 50% 50% tWC Figure 1. Serial Interface Timing 6 _______________________________________________________________________________________ Octal High-Voltage Transmit/Receive Switches ICC, IEE SUPPLY CURRENT vs. VCC, VEE SUPPLY VOLTAGE 1.5 1.0 0.5 2.00 0 2.5 3.0 3.5 4.0 4.5 5.0 MAX4936-39 toc02 ONE CHANNEL ON ICC, IEE SUPPLY CURRENT (mA) MAX4936-39 toc01 ICC, IEE SUPPLY CURRENT (mA) 2.0 ICC, IEE SUPPLY CURRENT vs. TEMPERATURE ONE CHANNEL ON 1.75 1.50 1.25 1.00 5.5 -40 -15 10 35 60 85 ICC_SHDN, IEE_SHDN SUPPLY SHUTDOWN CURRENT vs. TEMPERATURE COM_ TO NO_ SMALL-SIGNAL TRANSFER FUNCTION vs. FREQUENCY 0.10 0.05 0 0 14 28 42 56 -1.0 ICH = 3mA -1.5 70 0 5 10 15 COM_ TO NO_ IMPEDANCE vs. FREQUENCY COM_ TO NO_ CROSSTALK vs. FREQUENCY 5 ICH = 3mA 3 RNO_ = 200Ω RCOM_ = 200Ω -70 CROSSTALK (dB) ICH = 1.5mA 4 -60 MAX4936-39 toc05 COM_ TO NO_ IMPEDANCE (Ω) ICH = 1.5mA FREQUENCY (MHz) 8 6 -0.5 TEMPERATURE (°C) 9 7 RNO_ = 50Ω 20 MAX4936-39 toc06 0.15 0 COM_ TO NO_ ATTENUATION (dB) MAX4936-39 toc03 0.20 MAX4936-39 toc04 TEMPERATURE (°C) ICC_SHDN, IEE_SHDN SHUTDOWN CURRENT (µA) VCC, VEE SUPPLY VOLTAGE (V) -80 -90 2 1 -100 0 0 5 10 FREQUENCY (MHz) 15 20 1 10 FREQUENCY (MHz) _______________________________________________________________________________________ 7 MAX4936–MAX4939 Typical Operating Characteristics (VDD = +3V, VCC = +5V, VEE = -5V, ICH = 1.5mA, RCOM_ = 200I, RNO_ = 200I, f = 5MHz, VCLR = 0V, TA = +25NC, unless otherwise noted.) Typical Operating Characteristics (continued) (VDD = +3V, VCC = +5V, VEE = -5V, ICH = 1.5mA, RCOM_ = 200I, RNO_ = 200I, f = 5MHz, VCLR = 0V, TA = +25NC, unless otherwise noted.) PSRR_VEE RNO_ = 50Ω COM_ 0.06 0.04 VOLTAGE (V) -75 -80 NO_ 0.02 0 -0.02 -0.04 PSRR_VCC 0 COM_/NO_ FET (dB) RNO_ = 200Ω RCOM_ = 200Ω MAX4936-39 toc08 0.08 MAX4936-39 toc07 -70 COM_/NO_ FFT vs. FREQUENCY (2MHz GAUSSIAN SIGNAL AT COM_) RNO_ = 50Ω NO_ COM_ -20 MAX4936-39 toc09 COM_/NO_ SMALL SIGNAL vs. TIME (2MHz GAUSSIAN SIGNAL AT COM_) PSRR vs. FREQUENCY PSRR (dB) MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches -40 -60 -0.06 -85 -0.08 1 10 -80 -5 -4 FREQUENCY (MHz) -3 -2 -1 0 1 2 3 4 5 0 TIME (ms) 5 10 FREQUENCY (MHz) COM_/NO_ vs. TIME FOR CLR TOGGLING FROM VDD TO GND TO VDD HV_/COM_ vs. TIME MAX4936-39 toc11 MAX4936-39 toc10 COM_LOAD = 200Ω VHV_ 50V/div VCOM_ 5mV/div NO_LOAD = 200Ω 30pF COM_LOAD = 100Ω 100pF VCOM_ 50V/div 100ns/div VNO_ 5mV/div 200µs/div 8 _______________________________________________________________________________________ 15 Octal High-Voltage Transmit/Receive Switches LVEE8 LVCC7 NO7 LVEE7 LVCC6 NO6 LVEE6 LVCC5 NO5 LVEE5 LVEE4 NO4 LVCC4 LVEE3 NO3 LVCC3 LVEE2 NO2 LVCC2 LVEE1 TOP VIEW 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 NO8 NO1 49 27 LVCC8 LVCC1 50 26 DOUT LE 51 CLR 52 25 DIN MAX4936/MAX4938 GND 53 24 CLK N.C. 54 23 GND COM1 55 22 COM8 *EP 1 2 3 4 5 6 7 8 9 HV2 N.C. COM3 HV3 N.C. COM4 HV4 VDD VCC VEE GND HV5 COM5 N.C. HV6 COM6 N.C. HV7 COM7 LVCC2 NO2 LVEE2 LVCC3 NO3 LVEE3 LVCC4 NO4 LVEE4 LVEE5 NO5 LVCC5 LVEE6 NO6 LVCC6 LVEE7 NO7 LVCC7 LVEE8 21 HV8 COM2 + LVEE1 HV1 56 10 11 12 13 14 15 16 17 18 19 20 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 NO8 NO1 49 27 LVCC8 LVCC1 50 26 DOUT LE 51 CLR 52 25 DIN MAX4937/MAX4939 GND 53 24 CLK N.C. 54 23 GND COM1 55 22 COM8 *EP COM4 N.C. COM7 N.C. N.C. N.C. N.C. COM3 21 N.C. 10 11 12 13 14 15 16 17 18 19 20 COM6 N.C. 9 N.C. 8 N.C. 7 COM5 6 N.C. 5 GND 4 VEE 3 VCC 2 VDD 1 N.C. + COM2 N.C. 56 TQFN (5mm × 11mm) *CONNECT EP TO GND. Pin Description PIN MAX4936/ MAX4938 MAX4937/ MAX4939 NAME 1 1 COM2 2 — HV2 FUNCTION T/R Switch 2 Input. When the switch is on, low-voltage signals are passed through from COM2 to NO2, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 2 Input. COM2 follows HV2 when high-voltage signals are present on HV2. HV2 is isolated from COM2 when low-voltage signals are present on COM2. _______________________________________________________________________________________ 9 MAX4936–MAX4939 Pin Configuration MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches Pin Description (continued) PIN NAME FUNCTION MAX4936/ MAX4938 MAX4937/ MAX4939 3, 6, 15, 18, 54 2, 3, 5, 6, 8, 13, 15, 16, 18, 19, 21, 54, 56 N.C. 4 4 COM3 5 — HV3 7 7 COM4 8 — HV4 T/R Switch 4 Input. COM4 follows HV4 when high-voltage signals are present on HV4. HV4 is isolated from COM4 when low-voltage signals are present on COM4. 9 9 VDD Positive Logic Supply. Bypass VDD to GND with a 1FF or greater ceramic capacitor as close as possible to the device. 10 10 VCC Positive Analog Supply. Bypass VCC to GND with a 1FF or greater ceramic capacitor as close as possible to the device. 11 11 VEE Negative Analog Supply. Bypass VEE to GND with a 1FF or greater ceramic capacitor as close as possible to the device. 12, 23, 53 12, 23, 53 GND Ground 13 — HV5 T/R Switch 5 Input. COM5 follows HV5 when high-voltage signals are present on HV5. HV5 is isolated from COM5 when low-voltage signals are present on COM5. 14 14 COM5 16 — HV6 17 17 COM6 19 — HV7 20 20 COM7 21 — HV8 22 22 COM8 No Connection. Not internally connected. T/R Switch 3 Input. When the switch is on, low-voltage signals are passed through from COM3 to NO3, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 3 Input. COM3 follows HV3 when high-voltage signals are present on HV3. HV3 is isolated from COM3 when low-voltage signals are present on COM3. T/R Switch 4 Input. When the switch is on, low-voltage signals are passed through from COM4 to NO4, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 5 Input. When the switch is on, low-voltage signals are passed through from COM5 to NO5, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 6 Input. COM6 follows HV6 when high-voltage signals are present on HV6. HV6 is isolated from COM6 when low-voltage signals are present on COM6. T/R Switch 6 Input. When the switch is on, low-voltage signals are passed through from COM6 to NO6, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 7 Input. COM7 follows HV7 when high-voltage signals are present on HV7. HV7 is isolated from COM7 when low-voltage signals are present on COM7. T/R Switch 7 Input. When the switch is on, low-voltage signals are passed through from COM7 to NO7, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. T/R Switch 8 Input. COM8 follows HV8 when high-voltage signals are present on HV8. HV8 is isolated from COM8 when low-voltage signals are present on COM8. T/R Switch 8 Input. When the switch is on, low-voltage signals are passed through from COM8 to NO8, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. 10 ������������������������������������������������������������������������������������� Octal High-Voltage Transmit/Receive Switches PIN MAX4936/ MAX4938 MAX4937/ MAX4939 NAME FUNCTION 24 24 CLK Serial-Clock Input 25 25 DIN Serial-Data Input 26 26 DOUT Serial-Data Output 27 27 LVCC8 Inductor VCC Connection. Connect an inductor between LVCC8 and VCC to improve noise performance, otherwise connect LVCC8 to VCC. T/R Switch 8 Output. When the switch is on, low-voltage signals are passed through from COM8 to NO8, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO8 is limited with clamping diodes on MAX4936/MAX4937. 28 28 NO8 29 29 LVEE8 Inductor VEE Connection. Connect an inductor between LVEE8 and VEE to improve noise performance; otherwise, connect LVEE8 to VEE. 30 30 LVCC7 Inductor VCC Connection. Connect an inductor between LVCC7 and VCC to improve noise performance; otherwise, connect LVCC7 to VCC. T/R Switch 7 Output. When the switch is on, low-voltage signals are passed through from COM7 to NO7, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO7 is limited with clamping diodes on MAX4936/MAX4937. 31 31 NO7 32 32 LVEE7 Inductor VEE Connection. Connect an inductor between LVEE7 and VEE to improve noise performance; otherwise, connect LVEE7 to VEE. 33 33 LVCC6 Inductor VCC Connection. Connect an inductor between LVCC6 and VCC to improve noise performance; otherwise, connect LVCC6 to VCC. T/R Switch 6 Output. When the switch is on, low-voltage signals are passed through from COM6 to NO6, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO6 is limited with clamping diodes on MAX4936/MAX4937. 34 34 NO6 35 35 LVEE6 Inductor VEE Connection. Connect an inductor between LVEE6 and VEE to improve noise performance; otherwise, connect LVEE6 to VEE. 36 36 LVCC5 Inductor VCC Connection. Connect an inductor between LVCC5 and VCC to improve noise performance; otherwise, connect LVCC5 to VCC. T/R Switch 5 Output. When the switch is on, low-voltage signals are passed through from COM5 to NO5, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO5 is limited with clamping diodes on MAX4936/MAX4937. 37 37 NO5 38 38 LVEE5 Inductor VEE Connection. Connect an inductor between LVEE5 and VEE to improve noise performance; otherwise, connect LVEE5 to VEE. 39 39 LVEE4 Inductor VEE Connection. Connect an inductor between LVEE4 and VEE to improve noise performance; otherwise, connect LVEE4 to VEE. 40 40 NO4 T/R Switch 4 Output. When the switch is on, low-voltage signals are passed through from COM4 to NO4, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO4 is limited with clamping diodes on MAX4936/MAX4937. ______________________________________________________________________________________ 11 MAX4936–MAX4939 Pin Description (continued) MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches Pin Description (continued) PIN MAX4936/ MAX4938 MAX4937/ MAX4939 NAME FUNCTION 41 41 LVCC4 Inductor VCC Connection. Connect an inductor between LVCC4 and VCC to improve noise performance; otherwise, connect LVCC4 to VCC. 42 42 LVEE3 Inductor VEE Connection. Connect an inductor between LVEE3 and VEE to improve noise performance; otherwise, connect LVEE3 to VEE. T/R Switch 3 Output. When the switch is on, low-voltage signals are passed through from COM3 to NO3, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO3 is limited with clamping diodes on MAX4936/MAX4937. 43 43 NO3 44 44 LVCC3 Inductor VCC Connection. Connect an inductor between LVCC3 and VCC to improve noise performance; otherwise, connect LVCC3 to VCC. 45 45 LVEE2 Inductor VEE Connection. Connect an inductor between LVEE2 and VEE to improve noise performance; otherwise, connect LVEE2 to VEE. T/R Switch 2 Output. When the switch is on, low-voltage signals are passed through from COM2 to NO2, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO2 is limited with clamping diodes on MAX4936/MAX4937. 46 46 NO2 47 47 LVCC2 Inductor VCC Connection. Connect an inductor between LVCC2 and VCC to improve noise performance; otherwise, connect LVCC2 to VCC. 48 48 LVEE1 Inductor VEE Connection. Connect an inductor between LVEE1 and VEE to improve noise performance; otherwise, connect LVEE1 to VEE. T/R Switch 1 Output. When the switch is on, low-voltage signals are passed through from COM1 to NO1, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. NO1 is limited with clamping diodes on MAX4936/MAX4937. 49 49 NO1 50 50 LVCC1 51 51 LE Active-Low Latch-Enable Input. Drive LE low to change the contents of the latch and update the state of the switches. Drive LE high to hold the contents of the latch. 52 52 CLR Active-High Latch-Clear Input. Drive CLR high to clear the contents of the latch and disable all the switches. When CLR is driven high, the device enters shutdown mode. CLR does not affect the contents of the register. 55 55 COM1 T/R Switch 1 Input. When the switch is on, low-voltage signals are passed through from COM1 to NO1, while high-voltage signals are blocked. When the switch is off, both low-voltage and high-voltage signals are blocked. 56 — HV1 T/R Switch 1 Input. COM1 follows HV1 when high-voltage signals are present on HV1. HV1 is isolated from COM1 when low-voltage signals are present on COM1. — — EP Exposed Pad. Internally connected to GND. Connect EP to a large ground plane to maximize thermal performance. Do not use EP as the only GND connection. Inductor VCC Connection. Connect an inductor between LVCC1 and VCC to improve noise performance; otherwise, connect LVCC1 to VCC. 12 ������������������������������������������������������������������������������������� Octal High-Voltage Transmit/Receive Switches VDD VCC * HV_ MAX4936−MAX4939 (SINGLE CHANNEL) LVCC_ VEE COM_ NO_ ** LVEE_ VCC SPI LOGIC GND CLK DIN DOUT LE CLR VEE Detailed Description The MAX4936–MAX4939 are octal, high-voltage transmit/receive (T/R) switches. The T/R switches are based on a diode bridge topology, and the amount of current in the diode bridges can be programmed through an SPI interface. All devices feature a latch-clear input to asynchronously turn off all T/R switches and put the device into a low-power shutdown mode. The MAX4936/ SPI LOGIC D0 D1 The receive path for all devices is low impedance during low-voltage receive and high impedance during high-voltage transmit, providing protection to the receive circuitry. The low-voltage receive path is high bandwidth, low noise, low distortion, and low jitter. Each T/R switch can be individually programmed on or off, allowing these devices to also be used as receive path multiplexers. Serial Interface All the devices are controlled by a serial interface with a 12-bit serial shift register and transparent latch (Figure 2). Each of the first 4 data bits controls the bias current into the diode bridges (see Figure 3 and Table 2), while the remaining 8 data bits control a T/R switch (Table 1). Data on DIN is clocked with the most significant bit (MSB) first into the shift register on the rising edge of CLK. Data is clocked out of the shift register onto DOUT on the rising edge of CLK. DOUT reflects the status of DIN, delayed by 12 clock cycles (Figure 4). Transmit/Receive Switch REGISTER DIN The MAX4936/MAX4938 transmit path is low impedance during high-voltage transmit and high impedance during low-voltage receive, providing isolation between transmit and receive circuitry. The high-voltage transmit path is high bandwidth, low distortion, and low jitter. The MAX4936/MAX4937 feature clamping diodes to protect the receiver input from voltage spikes due to leakage currents flowing through the T/R switches during transmission. The MAX4938/MAX4939 do not have clamping diodes and rely on clamping diodes integrated in the receiver front-end. *LOW-VOLTAGE ISOLATION DIODES AVAILABLE ON MAX4936/MAX4938 ONLY. **OUTPUT CLAMP DIODES AVAILABLE ON MAX4936/MAX4937 ONLY. CLK MAX4938 include the T/R switch and grass-clipping diodes, performing both transmit and receive operations. The MAX4937/MAX4939 include just the T/R switch and perform the receive operation only. D10 D11 DOUT The T/R switch is based on a diode bridge topology. The amount of bias current into each diode bridge is adjustable by setting the S0–S3 switches through the serial interface (see Figure 3 and Table 2). Latch Enable (LE) LATCH CLR ON1 ON2 LE Figure 2. SPI Logic S2 S3 Drive LE logic-low to change the contents of the latch and update the state of the T/R switches (Figure 4). Drive LE logic-high to hold the contents of the latch and prevent changes to the switches’ states. To reduce noise due to clock feedthrough, drive LE logic-high while data is clocked into the shift register. After the data shift register is loaded with valid data, pulse LE logic-low to load the contents of the shift register into the latch. ______________________________________________________________________________________ 13 MAX4936–MAX4939 Functional Diagram MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches Latch Clear (CLR) LVCC (LVEE) S3 R3 S1 S2 R2 Drive CLR logic-high to reset the contents of the latch to zero and open all T/R switches. CLR does not affect the contents of the shift register. Once CLR is high again, and LE is driven low, the contents of the shift register are loaded into the latch. S0 R1 R0 Power-On Reset The devices feature a power-on-reset circuit to ensure all switches are off at power-on. The internal 12-bit serial shift register and latch are set to zero on power-up. DIODE BRIDGE Figure 3. Diode Bias Current Control LE CLK DIN D11 D10 D9 D1 MSB DOUT D11' D0 LSB D10' D9' D1' D0' D11'–D0' FROM PREVIOUS DATA POWER-UP DEFAULT: D11–D0 = 0 Figure 4. Latch-Enable Interface Timing 14 ������������������������������������������������������������������������������������� D11 Octal High-Voltage Transmit/Receive Switches CONTROL BITS DATA BITS D0 (LSB) D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 (MSB) L H FUNCTION LE CLR SW1 L L Off On SW2 SW3 SW4 SW5 SW6 SW7 SW8 S0 S1 S2 L L L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On L L L Off H L L On S3 L L L Off H L L On X X X X X X X X X X X X H L X X X X X X X X X X X X X H Hold Previous State Off Off Off Off Off Off Off Off Off Off Off Off L = Low, H = High, X = Don’t care. Table 2. Diode Bias Current SWITCHES RESISTOR COMBINATION RESISTORS (I) TYPICAL DIODE BRIDGE CURRENT (mA) vs. S[3:0] CONTROL BITS (*) S3 S2 S1 S0 R3 R2 R1 R0 (I) VCC = 3.0V VCC = 5.0V 0 0 0 0 350 700 1400 2800 — 0 0 0 0 0 1 350 700 1400 2800 2800 0.78 1.50 0 0 1 0 350 700 1400 2800 1400 1.58 3.00 0 0 1 1 350 700 1400 2800 933 2.36 4.50 0 1 0 0 350 700 1400 2800 700 3.14 6.00 0 1 0 1 350 700 1400 2800 560 3.98 7.50 0 1 1 0 350 700 1400 2800 467 4.72 9.00 0 1 1 1 350 700 1400 2800 400 5.50 10.50 1 0 0 0 350 700 1400 2800 350 6.28 12.00 1 0 0 1 350 700 1400 2800 311 7.08 13.50 1 0 1 0 350 700 1400 2800 280 7.86 15.00 1 0 1 1 350 700 1400 2800 255 8.64 16.50 1 1 0 0 350 700 1400 2800 233 9.42 18.00 1 1 0 1 350 700 1400 2800 215 10.22 19.50 1 1 1 0 350 700 1400 2800 200 11.00 21.00 1 1 1 1 350 700 1400 2800 187 11.78 22.50 *VEE = -VCC ______________________________________________________________________________________ 15 MAX4936–MAX4939 Table 1. Serial Interface Programming MAX4936–MAX4939 Octal High-Voltage Transmit/Receive Switches Applications Information For medical ultrasound applications, see Figures 5, 6, and 7. all devices, and drive LE logic-low to update all devices simultaneously. Drive CLR high to open all the switches simultaneously. Additional shift registers can be included anywhere in series with the device data chain. Ultrasound-Specific IMD3 Specification Unlike typical communications applications, the two input tones are not equal in magnitude for the ultrasound-specific IMD3 two-tone specification. In this measurement, F1 represents reflections from tissue and F2 represents reflections from blood. The latter reflections are typically 25dB lower in magnitude, and hence the measurement is defined with one input tone 25dB lower than the other. The IMD3 product of interest (F1 - (F2 - F1)) presents itself as an undesired Doppler error signal in ultrasound applications. See Figure 8. Logic Levels The digital interface inputs CLK, DIN, LE, and CLR are tolerant of up to +5.5V, independent of the VDD supply voltage, allowing compatibility with higher voltage controllers. Daisy-Chaining Multiple Devices Digital output DOUT is provided to allow the connection of multiple devices by daisy-chaining (Figure 9). Connect each DOUT to the DIN of the subsequent device in the chain. Connect CLK, LE, and CLR inputs of Supply Sequencing and Bypassing The devices do not require special sequencing of the VDD, VCC, and VEE supply voltages; however, analog switch inputs must be unconnected, or satisfy VEE P (VHV_, VCOM_, VNO_) P VCC during power up and power down. Bypass VDD, VCC, and VEE to GND with a 1FF ceramic capacitor as close as possible to the device. PCB Layout The pin configuration is optimized to facilitate a very compact physical layout of the device and its associated discrete components. A typical application for this device might incorporate several devices in close proximity to handle multiple channels of signal processing. The exposed pad (EP) of the TQFN-EP package provides a low thermal resistance path to the die. It is important that the PCB on which the device is mounted be designed to conduct heat from the EP. In addition, provide the EP with a low-inductance path to electrical ground. The EP must be soldered to a ground plane on the PCB, either directly or through an array of plated through holes. Application Diagrams HV MUX TRANSDUCERS HV MUX COM_ RELAY MUX SPI CONTROL CLK DIN DOUT CLR LE +3V +5V VDD VCC MAX4936/MAX4938 XMT HV_ NO_ GND RCV VEE HV MUX CONNECTORS -5V Figure 5. Ultrasound T/R Path with One Transmit per Receive Channel (One Channel Only) 16 ������������������������������������������������������������������������������������� Octal High-Voltage Transmit/Receive Switches XMT +3V +5V VDD VCC TRANSDUCERS HV MUX COM_ HV MUX RELAY MUX SPI CONTROL CLK DIN DOUT CLR LE MAX4937/MAX4939 NO_ GND RCV VEE HV MUX CONNECTORS -5V Figure 6. Ultrasound T/R Path with One Transmit per Receive Channel and External Isolation (One Channel Only) MAX4936 HV_ < ±100V DRIVER TRANSMIT PATH HV_ < ±100V TRANSDUCERS DRIVER VCC HV MUX VEE COM_ HV MUX NO_ < 500mV VCC RELAY MUX COM_ VEE LNA VCC HV MUX VEE CONNECTORS RECEIVE PATH NO_ < 500mV VCC VEE Figure 7. Ultrasound T/R Path with Multiple Transmits per Receive Channel ______________________________________________________________________________________ 17 MAX4936–MAX4939 Application Diagrams (continued) Octal High-Voltage Transmit/Receive Switches MAX4936–MAX4939 Application Diagrams (continued) -25dB ULTRASOUND IMD3 F1 - (F2 - F1) F1 F2 F2 + (F2 - F1) Figure 8. Ultrasound IMD3 Measurement Technique U1 DIN DIN DOUT U2 DIN MAX4936MAX4939 CLK CLK LE LE DOUT DIN MAX4936MAX4939 LE DOUT MAX4936MAX4939 CLK CLK CLR U_ CLR LE CLR CLR Figure 9. Interfacing Multiple Devices by Daisy-Chaining Chip Information PROCESS: BCDMOS Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-“ in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 56 TQFN-EP T56511+1 21-0187 90-0087 18 ������������������������������������������������������������������������������������� Octal High-Voltage Transmit/Receive Switches REVISION NUMBER REVISION DATE 0 9/10 Initial release 3/11 Updated the Diode Bridge Turn-Off Time and the NO_ On Capacitance in the Electrical Characteristics, updated Figure 7 1 DESCRIPTION PAGES CHANGED — 3, 4, 17 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2011 Maxim Integrated Products 19 Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX4936–MAX4939 Revision History