19-5786; Rev 2; 1/12 16-Channel, Linear, High-Voltage Analog Switches Features The MAX4968/MAX4968A are 16-channel, high-linearity, high-voltage, bidirectional SPST analog switches with 18I (typ) on-resistance. The devices are ideal for use in applications requiring high-voltage switching controlled by a low-voltage control signal, such as ultrasound imaging and printers. The MAX4968A provides integrated 40kI (typ) bleed resistors on each switch terminal to discharge capacitive loads. Using HVCMOS technology, these switches combine high-voltage bilateral MOS switches and low-power CMOS logic to provide efficient control of high-voltage analog signals. S Latch Free SOI HVCMOS Process Technology for High Performance and Robustness S No Dedicated High-Voltage Supplies Required S RON Flatness Guaranteed in Entire Input Range S Low-Power Dissipation S Low-Charge Injection and Voltage Spike S 25MHz Serial Interface (+2.5V to +5V) S 2nd Harmonic Distortion < -45dB at 2MHz ± 90V Pulse The MAX4968 is pin-to-pin compatible with the MAX14802 and Supertex HV2601. The MAX4968A is pin-to-pin compatible with the MAX14803 and Supertex HV2701. The only difference is the VPP positive supply voltage level. The MAX4968/MAX4968A require a low +10V (typ) voltage (VPP), whereas the MAX14802/MAX14803 and HV2601/HV2701 require a high +100V supply voltage. S Low Parasitic Capacitance Guarantees High Bandwidth S DC to 30MHz Small-Signal Analog Bandwidth (CLOAD = 200pF) S 500kHz to 20MHz High-Signal Analog Bandwidth (CLOAD = 200pF) In a typical ultrasound application, these devices do not require a dedicated high-voltage supply that implies a significant simplification of system requirement. The negative voltage supply can be shared with the transmitter, and the positive voltage supply is typically +10V. S Extended Input Range Up to 210VP-P S -80dB (typ) Off-Isolation at 5MHz (50I) S Shunt (Bleed) Resistors on Outputs (MAX4968A Only) The devices are available in the 48-pin LQFP package and are specified over the -40NC to +85NC extended temperature range. S Daisy-Chainable Serial Interface Applications Medical Ultrasound Imaging Nondestructive Testing (NDT)/Industrial Ultrasound Imaging Printers PART Ordering Information/Selector Guide TEMP RANGE SWITCH CHANNELS BLEED RESISTOR PIN-PACKAGE MAX4968ECM+ -40°C to +85°C 16 No 48 LQFP MAX4968AECM+ -40°C to +85°C 16 Yes 48 LQFP +Denotes a lead(Pb)-free/RoHS-compliant package. ________________________________________________________________ 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. MAX4968/MAX4968A General Description MAX4968/MAX4968A 16-Channel, Linear, High-Voltage Analog Switches ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) VDD Logic Supply Voltage Range...........................-0.3V to +6V VPP - VNN Supply Voltage................................................. +212V VPP Supply Voltage Range....................................-0.3V to +12V VNN Negative Supply Voltage.............................................-200V Logic Input Voltage Range (CLK, DIN, CLR)..........-0.3V to +6V Logic Input Voltage Range (LE).........................-0.3V to a minimum of (VPP + 0.3V) or 6V Logic Output Voltage Range (DOUT)....... -0.3V to (VDD + 0.3V) Analog Signal Range (SW_) ......... (VNN - 0.3V) to (VNN + 220V) Continuous Power Dissipation (TA = +70NC) LQFP (derate 22.7mW/NC above +70NC) ..................1818mW Operating Temperature Range........................... -40NC to +85NC 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) LQFP Junction-to-Ambient Thermal Resistance (qJA)...........44°C/W Junction-to-Case Thermal Resistance (qJC)................10°C/W Note 1: P ackage thermal resistances 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 = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLIES VDD Logic Supply Voltage VDD +2.37 +5.5 V VNN Supply Voltage VNN -200 0 V VPP Supply Voltage VPP +9.5 VDD Static Current IDDS +10 +10.5 V 4 FA VDD Dynamic Current IDD VDD = +5V, fCLK = 5MHz, fDIN = 2.5MHz 200 FA VNN Static Current INNS All switches remain on or off, SW_ = GND 10 25 FA VNN Supply Dynamic Current (All Channels Switching Simultaneously) INN VPP = +10V, VNN = -100V, fTURN_ON/OFF = 50kHz, SW_ = GND 3.3 5 mA VPP Supply Static Current IPPS All switches remain on or off, SW_ = GND 12 25 FA VPP Supply Dynamic Current (All Channels Switching Simultaneously) IPP VPP = +10V, VNN = -100V, fTURN_ON/OFF = 50kHz, SW_ = GND 4 6 mA VNN + 210 V 34 I SWITCH CHARACTERISTICS Analog Dynamic Signal Range VSW_ AC operation only, f > 500kHz Small-Signal On-Resistance RONS VPP = +10V, VNN = -100V, VSW_ = 0V, ISW_ = 5mA 2 VNN 18 16-Channel, Linear, High-Voltage Analog Switches (VDD = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2) PARAMETER SYMBOL Small-Signal On-Resistance Matching DRONS Small-Signal On-Resistance Flatness Switch Output Bleed Resistor Switch-Off Leakage CONDITIONS MIN TYP MAX UNITS VPP = +10V, VNN = -100V, ISW_ = 5mA 3 % RONF AC measured, fSW_ = 0.5MHz, VSW_ = 80VP-P, RLOAD = 50I, VPP = +10V, VNN = -100V 2 % RINT MAX4968A only ISW_(OFF) 30 VSW_ = 0V, switch off (MAX4968 only) 40 50 kI 0 1 FA Switch-Off DC Offset No load (MAX4968A only) -15 0 +15 mV Switch-On DC Offset No load (MAX4968A only) -15 0 +15 mV Switch Output Isolation Diode Current 300ns pulse width, 2% duty cycle 3.0 A SWITCH DYNAMIC CHARACTERISITICS Turn-On Time tON VSW_A = +1V, RL = 100I, VNN = -100V, from enable to VSW_B = +0.9V 2 5 Fs Turn-Off Time tOFF VSW_A = +1V, RL = 100I, VNN = -100V, from disable to VSW_B = +0.9V 2 3.5 Fs Maximum VSW_ Slew Rate dV/dt CL = 100pF Off-Isolation VISO f = 2MHz, RL = 50I -76 dB VCT f = 5MHz, RL = 50I Crosstalk 20 V/ns -76 dB SW_ Off-Capacitance CSW_(OFF) f = 1MHz, small signal close to zero 9 pF SW_ On-Capacitance CSW_ (ON) f = 1MHz, small signal close to zero 13 pF VSPK RL = 50I ±70 mV Large-Signal Analog Bandwidth (-3dB) fBW_L CLOAD = 200pF, 60V amplitude sinusoidal burst, 1% duty cycle 30 MHz Small-Signal Analog Bandwidth (-3dB) fBW_S CLOAD = 200pF, 100mV amplitude sinusoidal 50 MHz Q VPP = +10V, VNN = -100V, Figure 1 150 pC Output Voltage Spike Charge Injection LOGIC LEVELS Logic-Input Low Voltage VIL 0.75 VDD 0.75 Logic-Input High Voltage VIH Logic-Output Low Voltage VOL ISINK = 1mA Logic-Output High Voltage VOH ISOURCE = 1mA Logic-Input Capacitance CIN Logic-Input Leakage IIN V 0.4 VDD 0.4 V V 5 -1 V pF +1 FA 3 MAX4968/MAX4968A ELECTRICAL CHARACTERISTICS (continued) MAX4968/MAX4968A 16-Channel, Linear, High-Voltage Analog Switches ELECTRICAL CHARACTERISTICS (continued) (VDD = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 25 MHz TIMING CHARACTERISTICS (Figure 2) CLK Frequency fCLK DIN to CLK Setup Time tDS 8 ns DIN to CLK Hold Time tDH 3 ns CLK to LE Setup Time tCS 8 ns LE Low Pulse Width tWL 12 ns CLR High Pulse Width tWC 12 CLK Rise and Fall Times tR, tF CLK to DOUT Delay tDO ns 50 VDD = +5V Q10%, CDOUT = 15pF 28 VDD = +2.5V Q5%, CDOUT = 15pF 45 Note 2: All devices are 100% tested at TA = +85NC. Limits over the operating temperature range are guaranteed by design. 4 ns ns 16-Channel, Linear, High-Voltage Analog Switches VPP - 10V RL 100kΩ SW_A SW_B SW_A VOUT ILEAK ILEAK A SW_B A RL 100kΩ MAX4968 MAX4968A VPP VPP VDD VNN VNN GND 5V SW_B MAX4968 MAX4968A MAX4968 MAX4968A VPP VPP VDD VNN VNN GND SWITCH-OFF LEAKAGE 5V VPP VPP VDD VNN VNN GND DC OFFSET ON/OFF 5V tON/tOFF TEST CIRCUIT VIN = 10VP-P AT 5MHz VIN = 10VP-P AT 5MHz SW_A SW_A VOUT IID SW_B VOUT SW_A VOUT VNN MAX4968 MAX4968A SW_B SW_B 50Ω MAX4968 MAX4968A MAX4968 MAX4968A VPP VPP VDD VNN VNN GND VISO = 20log SW_A 50Ω SW_B RL SW_A 5V VPP VPP VDD VNN VNN GND 5V VPP VPP VDD VNN VNN GND ISOLATION DIODE CURRENT VOUT VIN VCT = 20log 5V VOUT VIN CROSSTALK OFF-ISOLATION +VSPK VOUT SW_A VOUT SW_A VOUT -VSPK 100pF 50Ω SW_B VCOM_ SW_B MAX4968 MAX4968A RL 1kΩ VPP VPP VDD VNN VNN GND 5V VPP VPP MAX4968 MAX4968A VDD VNN VNN GND Q = 1000pF x VOUT CHARGE INJECTION VIN SW_B SW_A 5V OUTPUT VOLTAGE SPIKE VOUT VIN 200pF 10mVP-P SW_B SW_A VOUT 200pF 60VP-P BURST (1% DUTY CYCLE) MAX4968 MAX4968A MAX4968 MAX4968A VPP VPP VDD VNN VNN GND SMALL-SIGNAL BANDWIDTH MEASUREMENT 5V VPP VPP VDD VNN VNN GND 5V LARGE-SIGNAL BANDWIDTH MEASUREMENT Figure 1. Test Circuits 5 MAX4968/MAX4968A Test Circuits/Timing Diagrams 16-Channel, Linear, High-Voltage Analog Switches MAX4968/MAX4968A Test Circuits/Timing Diagrams (continued) DIN DN+1 DN 50% LE 50% DN-1 50% 50% tWL tCS 50% CLK 50% tDH tDO tDS 50% DOUT tOFF OFF 90% SWITCH 10% ON CLR tON 50% 50% tWC Figure 2. Serial Interface Timing LE CLK D15 DIN D14 D13 D1 LSB MSB DOUT D15 D14 D13 DATA FROM PREVIOUS DATA BYTE POWER-UP DEFAULT: D[15:0] = 0 Figure 3. Latch-Enable Interface Timing 6 D0 D1 D0 D15 16-Channel, Linear, High-Voltage Analog Switches TURN-ON/TURN-OFF TIME vs.TEMPERATURE tON tOFF -40 -60 TA = +85°C TA = +25°C -80 1 35 85 60 0.01 0.1 10 TA = +85°C 1.5 TA = +25°C TA = -40°C -15 4.3 4.7 5.1 VNN = -100V 12 5.5 VNN = -40V -40 -15 10 VNN = -70V 35 60 VDD SUPPLY VOLTAGE (V) TEMPERATURE (°C) LOGIC POWER-SUPPLY CURRENT vs. SERIAL-CLOCK FREQUENCY HIGH-VOLTAGE SUPPLY CURRENT vs. OUTPUT SWITCH FREQUENCY TA = +25°C 300 200 TA = +-40°C 100 ALL SWITCHES SWITCHING 8 SUPPLY CURRENT (mA) TA = +85°C 400 10 MAX4968 toc06 500 6 0 4 6 8 10 12 14 16 18 20 SERIAL-CLOCK FREQUENCY(MHz) 85 IPP (TA = +85°C) IPP (TA = -40°C) IPP (TA = +25°C) 4 INN (TA = +85°C) 2 2 85 14 8 3.9 60 VPP = +10V 16 0 3.5 35 18 10 3.1 10 TEMPERATURE (°C) 0.5 0 -40 20 SUPPLY CURRENT (µA) 2.5 2.7 100 POSITIVE AND NEGATIVE POWER-SUPPLY CURRENT vs. TEMPERATURE MAX4968 toc04 3.0 2.3 ISW_(0FF) 0 1 LOGIC POWER-SUPPLY CURRENT vs. SUPPLY VOLTAGE 1.0 0.2 FREQUENCY (MHz) TEMPERATURE (°C) 2.0 0.4 MAX4968 toc05 10 0.6 MAX4968 toc07 -15 LOGIC POWER-SUPPLY CURRENT (µA) -40 0.8 TA = -40°C -100 0.001 0 MAX4968 toc03 SWITCH-OFF LEAKAGE CURRENT (µA) OFF-ISOLATION (dB) -20 3 1.0 MAX4968 toc02 0 MAX4968 toc01 4 LOGIC POWER-SUPPLY CURRENT (µA) TURN-ON/TURN-OFF TIME (µs) 5 2 SWITCH-OFF LEAKAGE CURRENT vs.TEMPERATURE OFF-ISOLATION vs. FREQUENCY INN (TA = +25°C) INN (TA = -40°C) 0 0 10 20 30 40 85 OUTPUT SWITCH FREQUENCY (kHz) 7 MAX4968/MAX4968A Typical Operating Characteristics (VDD = +3V, VPP = +10V, VNN = -100V, RL = 100I, CL = 100pF, TA = +25NC, unless otherwise noted.) MAX4968/MAX4968A 16-Channel, Linear, High-Voltage Analog Switches SW15B SW15A SW14B SW14A SW13B SW13A SW12B SW12A SW11B N.C. N.C. TOP VIEW SW11A Pin Configuration 36 35 34 33 32 31 30 29 28 27 26 25 N.C. SW10B 37 24 SW10A 38 23 DOUT SW9B 39 22 CLR SW9A 40 21 LE SW8B 41 20 CLK SW8A 42 19 DIN SW7B 43 18 VDD SW7A 44 17 GND SW6B 45 16 N.C. SW6A 46 15 VPP SW5B 47 14 N.C. SW5A 48 13 VNN MAX4968 MAX4968A 9 10 11 12 SW0A 8 SW0B 7 SW1A SW4A 6 SW1B N.C. SW4B 5 SW2A 4 SW2B 3 SW3A 2 SW3B 1 N.C. + LQFP (7mm × 7mm) Pin Description 8 PIN NAME FUNCTION PIN NAME 1, 2, 14, 16, 24, 35, 36 N.C. 15 VPP Positive Voltage Supply. Bypass VPP to GND with a 0.1FF or greater ceramic capacitor. 3 SW4B Analog Switch 4—Terminal 4 SW4A Analog Switch 4—Terminal 17 GND Ground 5 SW3B Analog Switch 3—Terminal 6 SW3A Analog Switch 3—Terminal 18 VDD Logic Supply Voltage. Bypass VDD to GND with a 0.1FF or greater ceramic capacitor. 7 SW2B Analog Switch 2—Terminal 8 SW2A Analog Switch 2—Terminal 19 DIN Serial-Data Input No Connection. Not connected internally. FUNCTION 9 SW1B Analog Switch 1 —Terminal 20 CLK Serial-Clock Input 10 SW1A Analog Switch 1—Terminal 21 Active-Low Latch-Enable Input 11 SW0B Analog Switch 0—Terminal 22 LE CLR 12 SW0A Analog Switch 0—Terminal 23 DOUT Serial-Data Output SW15B Analog Switch 15—Terminal VNN Negative High-Voltage Supply. Bypass VNN to GND with a 0.1FF or greater ceramic capacitor. 25 13 26 SW15A Analog Switch 15—Terminal 27 SW14B Analog Switch 14—Terminal Latch-Clear Input 16-Channel, Linear, High-Voltage Analog Switches PIN NAME PIN NAME 28 SW14A Analog Switch 14—Terminal 40 SW9A Analog Switch 9—Terminal 29 SW13B Analog Switch 13—Terminal 41 SW8B Analog Switch 8—Terminal 30 SW13A Analog Switch 13—Terminal 42 SW8A Analog Switch 8—Terminal 31 SW12B Analog Switch 12—Terminal 43 SW7B Analog Switch 7—Terminal 32 SW12A Analog Switch 12—Terminal 44 SW7A Analog Switch 7—Terminal 33 SW11B Analog Switch 11—Terminal 45 SW6B Analog Switch 6—Terminal 34 SW11A Analog Switch 11—Terminal 46 SW6A Analog Switch 6—Terminal 37 SW10B Analog Switch 10—Terminal 47 SW5B Analog Switch 5—Terminal 38 SW10A Analog Switch 10—Terminal 48 SW5A Analog Switch 5—Terminal 39 SW9B Analog Switch 9—Terminal FUNCTION Detailed Description The MAX4968/MAX4968A are 16-channel, high-linearity, high-voltage, bidirectional SPST analog switches with 18I (typ) on-resistance. The devices are ideal for use in applications requiring high-voltage switching controlled by a low-voltage control signal, such as ultrasound imaging and printers. The MAX4968A provides integrated 40kI (typ) bleed resistors on each switch terminal to discharge capacitive loads. Using HVCMOS technology, these switches combine high-voltage, bilateral MOS switches and low-power CMOS logic to provide efficient control of high-voltage analog signals. FUNCTION Analog Switch The devices can transmit analog signals up to 210VP-P, with an analog signal range from VNN to VNN + 210V. Before starting the high-voltage burst transmission (VP-P > +20V), the input voltage is required to be close to GND to allow a proper settling of the pass FET. The highvoltage burst frequency must be greater than 500kHz. Extremely long high-voltage bursts (VP-P > +10V) with duty cycle greater than 20% could result in signal degradation, especially for unipolar transmission. In general, this applies for burst transmission with a nonzero DC content. The MAX4968 is pin-to-pin compatible with the MAX14802 and Supertex HV2601. The MAX4968A is pin-to-pin compatible with the MAX14803 and Supertex HV2701. The only difference is the VPP positive supply voltage level. The MAX4968/MAX4968A require a low +10V (typ) voltage (VPP), whereas the MAX14802/MAX14803 and HV2601/HV2701 require a high +100V supply voltage. Low-voltage signal (VP-P < 10V) continuous-wave bipolar transmission is supported for frequencies greater than 500kHz. For very small signals, such as the small echoes in typical ultrasound imaging systems (VP-P < 10V), the devices are not limited to a low-frequency bandwidth and can transmit DC signals. In typical ultrasound applications, these devices do not require dedicated high-voltage supply, which implies a significant simplification of system requirement. The negative voltage supply can be shared with the transmitter and the positive voltage supply is typically +10V. The devices operate with a high-voltage supply VNN from -200V to 0, VPP supply of +10V (typ), and a logic supply VDD (+2.37V to +5.5V). Voltage Supplies 9 MAX4968/MAX4968A Pin Description (continued) MAX4968/MAX4968A 16-Channel, Linear, High-Voltage Analog Switches Bleed Resistors (MAX4968A) (Figure 3). Drive LE logic-high to freeze the contents of the latch and prevent changes to the switch states. To reduce noise due to clock feedthrough, drive LE logichigh 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. The MAX4968A features integrated 40kI (typ) bleed resistors to discharge capacitive loads such as piezoelectric transducers. Each analog switch terminal is connected to GND with a bleed resistor. Serial Interface The MAX4968/MAX4968A are controlled by a serial interface with a 16-bit serial shift register and transparent latch. Each of the 16 data bits controls a single analog switch (see 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 16 clock cycles (see Figures 2 and 3). Latch Clear (CLR) The MAX4968/MAX4968A feature a latch-clear input. Drive CLR logic-high to reset the contents of the latch to zero and open all switches. CLR does not affect the contents of the data shift register. Pulse LE logic-low to reload the contents of the shift register into the latch. Power-On Reset The MAX4968/MAX4968A feature a power-on-reset circuit to ensure all switches are open at power-on. The internal 16-bit serial shift register and latch are set to zero on power-up. Latch Enable (LE) Drive LE logic-low to change the contents of the latch and update the state of the high-voltage switches Table 1. Serial Interface Programming (Notes 1–6) CONTROL BITS DATA BITS D0 (LSB) D1 D2 D3 D4 D5 D6 D7 LE CLR L L L Off H L L On L L Off On L H SW0 SW1 SW2 SW3 L L L L L Off H L L On L L Off On L H SW4 SW5 L L L L L Off H L L On L L Off On L H 10 FUNCTION SW6 SW7 L L L L L Off H L L On L L L Off H L L On X X X X X X X X H L X X X X X X X X X H Hold Previous State Off Off Off Off Off Off Off Off 16-Channel, Linear, High-Voltage Analog Switches CONTROL BITS DATA BITS D8 D9 D10 D11 D12 D13 D14 D15 (MSB) L H FUNCTION LE CLR SW8 SW9 SW10 SW11 SW12 SW13 SW14 SW15 L L Off On 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 H L L X X X X X X X X H L X X X X X X X X X H Off On Hold Previous State Off Off Off Off Off Off Off Off Note 1: The 16 switches operate independently. Note 2: Serial data is clocked in on the rising edge of CLK. Note 3: The switches go to a state retaining their present condition on the rising edge of LE. When LE is low, the shift register data flows through the latch. Note 4: DOUT is high when switch 15 is on. Note 5: Shift register clocking has no effect on the switch states if LE is high. Note 6: The CLR input overrides all other inputs. Applications Information In typical ultrasound applications, the MAX4968/MAX4968A do not require dedicated high-voltage supplies; the negative voltage supply can be shared with the transmitter and the positive voltage supply is typically +10V. See Figures 5, 6, and 7 for medical ultrasound applications. Logic Levels The MAX4968/MAX4968A digital interface inputs CLK, DIN, LE, and CLR operate on the VDD logic supply voltage. Daisy-Chaining Multiple Devices Digital output DOUT is provided to allow the connection of multiple MAX4968/MAX4968A devices by daisy- chaining (Figure 4). Connect each DOUT to the DIN of the subsequent device in the chain. Connect CLK, LE, and CLR inputs of 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 MAX4968/MAX4968A daisy-chain. Supply Sequencing and Bypassing The MAX4968/MAX4968A do not require special sequencing of the VDD, VPP, and VNN supply voltages. Bypass VDD, VPP, and VNN to GND with a 0.1FF ceramic capacitor as close as possible to the device. Note: Keep LE low during power-up. 11 MAX4968/MAX4968A Table 1. Serial Interface Programming (Notes 1–6) (continued) 16-Channel, Linear, High-Voltage Analog Switches MAX4968/MAX4968A Application Diagrams U11 U10 DIN1 CLK LE DOUT DIN CLK MAX4968 MAX4968A DOUT DIN CLK MAX4968 MAX4968A MAX4968 MAX4968A LE CLR CLR DOUT DIN CLK LE LE U1n CLR CLR U21 U20 DIN2 DOUT DIN MAX4968 MAX4968A MAX4968 MAX4968A MAX4968 MAX4968A CLK CLK LE LE LE Figure 4. Interfacing Multiple Devices by Daisy-Chaining CLR DOUT DIN CLK CLR 12 DOUT DIN U2n CLR 16-Channel, Linear, High-Voltage Analog Switches PROBES MAINFRAME HIGH-VOLTAGE TRANSMIT 1 PER CHANNEL PROBE SELECTION 2 TO 4 PROBES CABLE 1 PER CHANNEL TRANSDUCERS 2 TO 4 PER CHANNEL ±1 TO 2A MAX ±100V MAX RELAY 1 RELAY/CH/PROBE PROBE A HIGH-VOLTAGE ANALOG SWITCHES 2 TO 4 PER CHANNEL PROBE B +V 10mA TYP LOW-VOLTAGE RECEIVE 64 TO 128 CHANNELS PROBE C ±1V MAX HIGHVOLTAGE ISOLATION -V PROBE D Figure 5. Medical Ultrasound Application—High-Voltage Analog Switches in Probe 13 MAX4968/MAX4968A Application Diagrams (continued) 16-Channel, Linear, High-Voltage Analog Switches MAX4968/MAX4968A Application Diagrams (continued) PROBES MAINFRAME HIGH-VOLTAGE TRANSMIT 1 PER CHANNEL HIGH-VOLTAGE ANALOG SWITCHES 2 TO 4 PER CHANNEL PROBE SELECTION 2 TO 4 PROBES CABLE 2 TO 4 PER CHANNEL ±1 TO 2A MAX ±100V MAX +V 10mA TYP LOW-VOLTAGE RECEIVE 64 TO 128 CHANNELS RELAYS 2 TO 4 RELAYS/CH/PROBE PROBE A ±1V MAX HIGHVOLTAGE ISOLATION -V PROBE B PROBE C PROBE D Figure 6. Medical Ultrasound Application—High-Voltage Analog Switches in Mainframe 14 TRANSDUCERS 2 TO 4 PER CHANNEL 16-Channel, Linear, High-Voltage Analog Switches PROBES MAINFRAME HIGH-VOLTAGE TRANSMIT 2 TO 4 PER CHANNEL PROBE SELECTION 2 TO 4 PROBES CABLE TRANSDUCERS 2 TO 4 PER CHANNEL 2 TO 4 PER CHANNEL ±1 TO 2A MAX ±100V MAX RELAYS 2 TO 4 RELAYS/CH/PROBE LOW-VOLTAGE RECEIVE 64 TO 128 CHANNELS +V PROBE A 10mA TYP -V ±1V MAX PROBE B +V -V +V -V +V PROBE C -V +V -V +V -V PROBE D +V -V +V -V HIGH-VOLTAGE ISOLATION AND CHANNEL SELECT 2 TO 4 PER CHANNEL Figure 7. Medical Ultrasound Application—Multiple Transmit and Isolation per Receiver Channel 15 MAX4968/MAX4968A Application Diagrams (continued) 16-Channel, Linear, High-Voltage Analog Switches MAX4968/MAX4968A Functional Diagram VDD VPP LATCH LEVEL SHIFTER CLR DIN SW0B * * VNN SW0A VNN MAX4968 MAX4968A 16-BIT SHIFT REGISTER CLK DOUT LATCH LEVEL SHIFTER SW15B * VNN SW15A * VNN LE GND VNN *BLEED RESISTORS AVAILABLE ON THE MAX4968A ONLY. Chip Information PROCESS: BiCMOS 16 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. 48 LQFP C48+6 21-0054 90-0093 16-Channel, Linear, High-Voltage Analog Switches REVISION NUMBER REVISION DATE 0 3/11 Initial release 1 5/11 Removed future product asterisk from MAX4968 in Ordering Information, corrected Off-Isolation specification in Electrical Characteristics 2 1/12 Updated VNN specifications in Absolute Maximum Ratings and Electrical Characteristics supply voltage and VNN static current specifications DESCRIPTION PAGES CHANGED — 1, 3 2, 3, 4, 9 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 © 2012 Maxim Integrated Products 17 Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX4968/MAX4968A Revision History