MAX4896 Space-Saving, 8-Channel Relay/Load Driver General Description The MAX4896 8-channel relay and load driver is designed for medium voltage applications up to 50V. This device is offered in a 20-pin, 5mm x 5mm TQFN package, resulting in substantial board space savings. The MAX4896 8-channel relay driver offers built-in inductive kickback protection, drive for latching/nonlatching or dual-coil relays, and open-load and short-circuit fault detection.The MAX4896 also protects against overcurrent conditions. Each independent open-drain output features a 3 (typ) on-resistance, and is guaranteed to sink 200mA of load current (VS 4.5V). A built-in overvoltage protection clamp handles kickbackvoltage transients, which are common when driving inductive loads. Thermal-shutdown circuitry shuts off all outputs (OUT_) when the junction temperature exceeds +160C. The MAX4896 employs a reset input that allows the user to turn off all outputs simultaneously with a single control line. The MAX4896 includes a 10MHz SPITM-/QSPITM-/ MICROWIRETM-compatible serial interface. The serial interface is compatible with TTL-/CMOS-logic voltage levels and operates with a single +2.7V to +5.5V supply. In addition, the SPI output data can be used for diagnostics purposes including open-load and shortcircuit fault detection. The MAX4896 is offered in the extended (-40C to +85C) and automotive (-40C to +125C) operating temperature ranges. Typical Operating Circuit 0.1F INT C VRELAY RELAY COIL 1 VS OUT1 FLAG RESET SCLK CS RELAY COIL 8 DIN SLPD OUT8 GND PGND Pin Configuration appears at end of data sheet. 19-3843; Rev 4; 5/14 * VS 3.6V 100mA Built-In Output Clamp Protects Against Inductive Kickback +2.7V to +5.5V Logic Supply Voltage RESET Input Turns Off All Outputs Simultaneously Built-in Power-On Reset Automotive Temperature Range (-40C to +125C) SPI-/QSPI-/MICROWIRE-Compatible Serial Interface Serial Digital Output for Daisy Chaining and Diagnostics FLAG Output for P Interrupt Open-Load and Short-Circuit Detection and Protection Thermal Shutdown Low 100A (max) Quiescent Supply Current Space-Saving, 5mm x 5mm, 20-Pin TQFN Package Industrial Equipment ATE White Goods Power-Grid Monitoring and Protection Equipment Ordering Information PART VRELAY MAX4896 DOUT Supports Up to 50V Continuous Drain-to-Source Voltage Guaranteed Drive Current: * VS 4.5V 200mA (All Channels On) 410mA (Individual Channels) Applications VCC = 2.7V TO 5.5V PDCD Features TEMP RANGE PIN-PACKAGE MAX4896ETP+ -40C to +85C 20 TQFN-EP* (5mm x 5mm) MAX4896ATP+ -40C to +125C 20 TQFN-EP* (5mm x 5mm) *EP = Exposed pad. +Denotes lead(Pb)-free/RoHS-compliant package. SPI and QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. MAX4896 Space-Saving, 8-Channel Relay/Load Driver Absolute Maximum Ratings (All voltages referenced to GND.) VS..........................................................................-0.3V to +7.0V OUT_................................................................... (-0.3V to +50V) Continuous OUT_ Voltage ..................................................+50V CS, SCLK, DIN, RESET, SPLD, PDCD................-0.3V to +7.0V DOUT...........................................................-0.3V to (VS + 0.3V) PGND to GND.................................................... (-0.3V to +0.3V) Continuous OUT_ Current, TA = +25C (Note 1) All Outputs On...............................................................210mA Single Output On...........................................................420mA Continuous Power Dissipation (TA = +70C) 20-Pin TQFN (derate 21.3mW/C above +70C) ......1702mW Maximum Output Clamp Energy (EOUT_)........................... 30mJ Operating Temperature Range.......................... -40C to +125C Junction Temperature.......................................................+150C Storage Temperature Range............................. -65C to +150C Lead Temperature (soldering, 10s).................................. +300C Soldering Temperature (reflow)........................................+260C 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 2) 20 TQFN-EP Junction-to-Ambient Thermal Resistance (JA)...........29C/W Junction-to-Case Thermal Resistance (JC)..................2C/W Note 1: Maximum continuous current at a given temperature must be calculated such that the maximum continuous power dissipation for the package is not exceeded. Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (VS = +2.7V to +5.5V, TA = -40C to +125C, unless otherwise noted. Typical values are at TA = +25C.) (Note 3) PARAMETER SYMBOL Operating Voltage VS Quiescent Current ICC Dynamic Average Supply Current Thermal Shutdown Thermal-Shutdown Hysteresis Power-On Reset Power-On-Reset Hysteresis IS CONDITIONS MIN TYP 2.7 IOUT_ = 0, logic inputs = 0 or VS, RESET = low MAX UNITS 5.5 V VS = 3.6V 5 70 VS = 5V 10 100 fSCLK = 10MHz, fDIN = 0.5 x fCLK, COUT = 50pF, VS = 5.5V 6 A mA TSHD +160 C TSHDH 20 C VRST VS falling 1.8 VRSTH 2.05 2.3 140 V mV DIGITAL INPUTS (SCLK, DIN, CS, RESET, PDCD, SPLD) Input Logic-High Voltage VIH Input Logic-Low Voltage VIL Input Logic Hysteresis VHYST Input Leakage Currents ILEAK Input Capacitance www.maximintegrated.com CIN VS = 2.7V to 3.6V 2.0 VS = 4.5V to 5.5V 2.4 V VS = 2.7V to 3.6V 0.6 VS = 4.5V to 5.5V 0.8 230 Input voltages = 0 or +5.5V -1 mV +1 10 V A pF Maxim Integrated 2 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Electrical Characteristics (continued) (VS = +2.7V to +5.5V, TA = -40C to +125C, unless otherwise noted. Typical values are at TA = +25C.) (Note 3) PARAMETER SYMBOL CONDITIONS MIN TYP MAX 5 6 UNITS RELAY OUTPUT DRIVERS (OUT1-OUT8) IOUT = 50mA, VS = 2.7V OUT_ ON Resistance RON IOUT = 100mA, VS = 4.5V IOUT Off-Leakage Current ILEAK OUT Clamping Voltage VCLAMP OUT Current-Limit Threshold ILIM OUT Capacitance TJ = +25C TJ = +125C 11 TJ = +150C 12 TJ = +25C 3 TJ = +125C 4 7 TJ = +150C 8 PDCD = high or RESET = low, all outputs Off -1 +1 A (Note 4) 50 75 V VS 4.5V 400 960 mA VOUT = 16V, f = 1MHz 30 pF DIAGNOSTIC Open-Load Detection Voltage Threshold VDS(OL) Open-Load Detection-VoltageThreshold Hysteresis VDS(OLH) OUT_ Pulldown Current Fault Delay/Filtering Time IPD(OL) tD(FAULT) DIGITAL OUTPUT (DOUT, FLAG) DOUT Low Voltage VOL DOUT High Voltage VOH OUT_ falling 0.75 1 1.15 40 V mV PDCD = low 150 300 500 A From rising edge at CS at 50% to valid diagnostic data 30 90 280 s 2.7V VS 3.6V, ISINK = 0.3mA 0.4 4.5V VS 5.5V, ISINK = 0.5mA 0.4 2.7V VS 3.6V, ISOURCE = 0.25mA VS - 0.5 4.5V VS 5.5V, ISOURCE = 0.4mA VS - 0.5 FLAG Low Voltage ISINK = 0.5mA FLAG Off-Leakage Current 4.5V VS 5.5V, VFLAG = 5.5V -1 V V 0.4 V +1 A TIMING Turn-On Time (OUT_) Turn-Off Time (OUT_) www.maximintegrated.com tON tOFF From rising edge of CS at 50% to VOUT_ = 90%VP, VP = 15V, RL = 300, CL = 50pF, 2.7V VS < 3.6V 20 From rising edge of CS at 50% to VOUT_ = 90%VP, VP =16V, RL = 150, CL = 50pF, 4.5V VS 5.5V 10 From rising edge of CS at 50% to VOUT_ = 10%VP, VP = 15V, RL = 300, CL = 50pF, 2.7V VS < 3.6V 15 From rising edge of CS at 50% to VOUT_ = 90%VP, VP = 16V, RL = 150, CL = 50pF, 4.5V < VS 5.5V 10 s s Maxim Integrated 3 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Electrical Characteristics (continued) (VS = +2.7V to +5.5V, TA = -40C to +125C, unless otherwise noted. Typical values are at TA = +25C.) (Note 3) PARAMETER SYMBOL CONDITIONS TA = +85C SCLK Frequency fSCLK TA = +125C Cycle Time tCH + tCL CS Fall-to-SCLK Rise Setup tCSS CS Rise-to-SCLK Hold tCSH SCLK High Time tCH SCLK Low Time tCL Data Setup Time tDS Data Hold Time tDH SCLK Fall-to-DOUT Valid tDO 2.7V VS < 3.6V MIN 0 4.5V VS 5.5V 2.7V VS 3.6V MAX 0 4.5V VS 5.5V UNITS 6 11 5 MHz 10 2.7V VS 3.6V 200 4.5V VS 5.5V 100 2.7V VS 3.6V 100 4.5V VS 5.5V 50 2.7V VS 3.6V 100 4.5V VS 5.5V 50 2.7V VS 3.6V 80 4.5V VS 5.5V 40 2.7V VS 3.6V 80 4.5V VS 5.5V 40 2.7V VS 3.6V 40 4.5V VS 5.5V 20 2.7V VS 3.6V 5 4.5V VS 5.5V 0 50% of SCLK to 20% of VS falling edge, CL = 50pF, 50% at SCLK to 80% of VS rising edge TYP 2.7V VS 3.6V ns ns ns ns ns ns ns 70 ns 4.5V VS 5.5V 30 Rise Time (DIN, SCLK, CS, RESET) tSCR 20% of VS to 70% of VS, CL = 50pF (Note 5) 2.7V VS 3.6V 2 4.5V VS 5.5V 2 Fall Time (DIN, SCLK, CS, RESET) tSCF 20% of VS to 70% of VS, CL = 50pF (Note 5) 2.7V VS 3.6V 2 4.5V VS 5.5V 2 RESET Min Pulse Width tRW 70 s s ns Note 3: Specifications at -40C are guaranteed by design and not production tested. Note 4: The output stages are compliant with the transient immunity requirements, as specified in ISO 7637 Part 3 with test pulses 1, 2, 3a, and 3b. Note 5: Guaranteed by design. www.maximintegrated.com Maxim Integrated 4 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Typical Operating Characteristics (TA = +25C, unless otherwise noted.) TA = -40C VS = 5V 4.0 VS = 3.3V 3.1 3.5 3.9 4.3 4.7 5.5 0.1 1 VS = 3.3V 4 3 VS = 5V 2 VS = 2.7V 5 VS = 3.3V VS = 5V 4 3 VS = 5.5V VS = 5.5V 2 1 -40 -25 -10 5 20 35 50 65 80 95 110 125 MAX4896 toc03 3.1 3.5 3.9 4.3 4.7 5.1 2.14 2.12 2.10 2.08 2.06 2.04 2.02 2.00 -40 -25 -10 5 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) OUTPUT OFF LEAKAGE CURRENT vs. SUPPLY VOLTAGE OUT LEAKAGE CURRENT vs. TEMPERATURE INPUT LOGIC THRESHOLD vs. SUPPLY VOLTAGE MAX4896 toc07 80 VOUT = 50V 70 60 50 VOUT = 24V 40 30 VOUT = 12V 20 100 PDCD = VS 10 1 0.1 0.01 5.5 POWER-ON RESET VOLTAGE vs. TEMPERATURE TEMPERATURE (C) 90 VOUT = 50V VOUT = 24V VOUT = 12V 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 10 0 2.7 TEMPERATURE (C) 100 OUTPUT OFF LEAKAGE (pA) ON-RESISTANCE vs. TEMPERATURE IOUT_SINK = 100mA IOUT_SINK = 50mA SUPPLY VOLTAGE (V) MAX4896 DS toc08 1 2.0 10 6 VS = 2.7V 5 2.5 VS = 2.7V 7 RON () RON () 6 8 OUT LEAKAGE CURRENT (nA) 7 IOUT_SINK = 50mA 4.0 fCLK (MHz) MAX4896 toc04 8 4.5 3.0 SUPPLY VOLTAGE (V) ON-RESISTANCE vs. TEMPERATURE IOUT_SINK = 100mA 5.0 3.5 3.0 2.5 5.1 5.5 3.5 2.0 2.7 MAX4896 toc02 4.5 6.0 MAX4896 DS toc06 1 0 TA = +25C 5.0 6.5 MAX4896 toc09 4 3 2 7.0 RON () TA = +125C 7 6 5 TA = +85C fDIN = 0.5 x fCLK INPUT LOGIC THRESHOLD (V) 8 5.5 POWER-ON-RESET VOLTAGE (V) 9 6.0 ON-RESISTANCE vs. SUPPLY VOLTAGE SUPPLY CURRENT vs. fCLK MAX4896 toc05 ALL LOGIC INPUTS = VS SUPPLY CURRENT (mA) QUIESCENT CURRENT (A) 12 11 10 MAX4896 toc01 QUIESCENT CURRENT vs. SUPPLY VOLTAGE 0.001 2.7 3.1 3.5 3.9 4.3 4.7 SUPPLY VOLTAGE (V) www.maximintegrated.com 5.1 5.5 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) 0.50 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 SUPPLY VOLTAGE (V) Maxim Integrated 5 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Typical Operating Characteristics (continued) (TA = +25C, unless otherwise noted.) tOFF 1.5 1.0 tON 0.5 66.0 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.0 2.5 tOFF 2.0 1.5 1.0 0 4.7 4.9 5.1 700 650 TA = +85C 600 550 TA = +125C 500 5.3 400 5.5 4.5 4.7 4.9 5.1 5.3 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) OUT CLAMP VOLTAGE vs. TEMPERATURE BACK-EMF CLAMPING WITH STANDARD +12V RELAY BACK-EMF CLAMPING WITH STANDARD +24V RELAY VS = 3.3V VS = 5V 65.6 MAX4896 toc14 5.5 MAX4896 toc15 RESET (2V/div) 65.4 MAX4896 toc12 TA = +25C 450 tON 4.5 TA = -40C 750 SUPPLY VOLTAGE (V) 65.8 0UT CLAMP VOLTAGE (V) 3.5 0.5 MAX4896 toc13 0 4.0 OUT_ CURRENT LIMIT vs. SUPPLY VOLATGE 800 OUTPUT CURRENT LIMIT (mA) 2.0 RL = 150 CL = 50pF VOUT = 50V 4.5 MAX4896 toc11 tON/tOFF DELAY TIME (ms) 2.5 TURN-ON/TURN-OFF DELAY TIME vs. SUPPLY VOLTAGE 5.0 tON/tOFF DELAY TIME (s) RL = 300 CL = 50pF VOUT = 15V MAX4896 toc10 3.0 TURN-ON/TURN-OFF DELAY TIME vs. SUPPLY VOLTAGE RESET 5V/div 65.2 65.0 64.8 64.6 64.4 64.0 OUT (20V/div) OUT (20V/div) 64.2 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (C) www.maximintegrated.com 1ms/div 1ms/div Maxim Integrated 6 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Pin Description PIN NAME 1 RESET 2 CS Chip Select Input. Drive CS low to select the device. When CS is low, data at DIN is clocked into the 8-bit shift register on SCLK's rising edge. Drive CS from low to high to latch the data to the registers. 3 DIN Serial Data Input 4 SCLK Serial Clock Input 5 DOUT Serial Data Output. DOUT is the output of the 8-bit shift register. This output can be used to daisy chain multiple MAX4896s. The data at DOUT appears synchronous to SCLK's falling edge. 6 PDCD Pulldown Current Disable. Drive PDCD high to disable OUT's pulldown current source. Drive PDCD low to enable OUT_ pulldown current source. PDCD must be low to detect an open-load fault. 7 SPLD Short-Protection Latch-Off Disable Input. Drive SPLD high to disable the built-in short-circuit protection latch-off feature. When SPLD is low, an overloaded channel is turned off immediately. See the Output Short-Circuit/Current-Limiting Protection section. 8 OUT8 Open-Drain Output 8. Connect OUT8 to the low side of a relay coil. OUT8 is pulled to PGND when activated and is otherwise high impedance. 9 OUT9 Open-Drain Output 7. Connect OUT7 to the low side of a relay coil. OUT7 is pulled to PGND when activated and is otherwise high impedance. 10, 16 PGND Power Ground. PGND is the ground return path for the output sinks. Connect PGND pins together and to GND. 11 OUT6 Open-Drain Output 6. Connect OUT6 to the low side of a relay coil. OUT6 is pulled to PGND when activated and is otherwise high impedance. 12 OUT5 Open-Drain Output 5. Connect OUT5 to the low side of a relay coil. OUT5 is pulled to PGND when activated and is otherwise high impedance. 13 GND Ground 14 OUT4 Open-Drain Output 4. Connect OUT4 to the low side of a relay coil. OUT4 is pulled to PGND when activated and is otherwise high impedance. 15 OUT3 Open-Drain Output 3. Connect OUT3 to the low side of a relay coil. OUT3 is pulled to PGND when activated and is otherwise high impedance. 17 OUT2 Open-Drain Output 2. Connect OUT2 to the low side of a relay coil. OUT2 is pulled to PGND when activated and is otherwise high impedance. 18 OUT1 Open-Drain Output 1. Connect OUT1 to the low side of a relay coil. OUT1 is pulled to PGND when activated and is otherwise high impedance. 19 VS 20 FLAG -- EP www.maximintegrated.com FUNCTION Reset Input. Drive RESET low to clear all latches and registers (all outputs are turned off). All OUT pulldown currents are disabled when RESET = low. Input Supply Voltage. Bypass VS to GND with a 0.1F capacitor. Open-Drain Fault Output. FLAG asserts low when a fault occurs at OUT1-OUT8. Exposed Paddle. Internally connected to GND. Connect to a large PCB ground plane to improve thermal dissipation. Enhances thermal conductivity; not intended as an electrical connection point. Maxim Integrated 7 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Detail Description The MAX4896 is an 8-channel relay and load driver for medium voltage applications up to 50V. The MAX4896 features built-in inductive kickback protection, drive for latching/nonlatching, or dual-coil relays and an internal register for detecting open-load and short-circuit faults. Each independent open-drain output features a 3 onresistance and is guaranteed to sink 400mA at VS 4.5V, and 100mA at VS 3.6V. The MAX4896 also incorporates a logic input (PDCD) that allows the device to continue operating when an overcurrent condition lasts longer than the 280s (max) fault delay time. A built-in overvoltage protection clamp handles kickback voltage transients, which are common when driving inductive loads. Thermal-shutdown circuitry shuts off all outputs (OUT_) when the junction temperature exceeds +160C. The MAX4896 employs a reset input that allows the user to turn off all outputs simultaneously with a single control line. The MAX4896 includes a 10MHz SPI-/QSPI-/MICROWIRE compatible serial interface. The serial interface is compatible with TTL-/CMOS-logic voltage levels and operates with a single +2.7V to +5.5V supply. Serial Interface The serial interface consists of an 8-bit input shift register, a parallel latch (output control register) controlled by SCLK and CS, and an output status register containing diagnostics information. The input to the shift register is an 8-bit word. Each data bit controls one of the eight outputs, with the most significant bit (D7) corresponding to OUT8, and the least significant bit (D0) corresponding to OUT1 (see Table 1). When CS is low, data at DIN is clocked into the shift register synchronously with SCLK's rising edge. Driving CS from low to high latches the data in the shift register to the output control register. DOUT is the output of the internal output status register for diagnostics purposes (see Figure 2 and Tables 2 and 3). Status data for each channel is transferred to the shift register at the falling edge of CS. The data bits contained in the shift register are then transferred to the DOUT output synchronously with SCLK's falling edge. While CS is low, the switches always remain in their previous states. Drive CS high after 8 bits of data have been shifted in to update the output state, and to further inhibit data from entering the shift register. When CS is high, transitions at DIN and SCLK have no effect on the output, and the first input bit (D7) is present at DOUT. If the number of data bits entered while CS is low is greater or less than 8, the shift register contains only the last 8 data bits, regardless of when they were entered. The 3-wire serial interface is compatible with SPI, QSPI, and MICROWIRE standards. The latch that drives the analog output stages is updated on the rising edge of CS, regardless of SCLK's state. Diagnostic Information Figure 1. Serial Interface The MAX4896 contains an internal output status register used for diagnostics information for each output (see Tables 1, 2, and 3). When a fault condition is detected at any channel for longer than the minimum fault-filtering time (tD(FAULT)_min), the fault information is latched into the corresponding position in the output status register (see Table 2), and the FLAG asserts. Status/diagnostics data for each channel in the output status register is transferred to the output shift register at the falling edge of CS. While CS is low, the diagnostics bits are then transferred to DOUT synchronously with SCLK's falling edge. A rising edge at CS resets the output status register data. During normal operation,the output status bit is the same as the DIN bit (DO1 = D1, DO2 = D2). When the MAX4896 is operating with a fault condition, the output status bit is the inverse of the DIN bit (DO1 = 0, D1 = 1). www.maximintegrated.com Maxim Integrated 8 OUTPUT STATUS REGISTER (OSR) LATCHED ON CS: DIN SCLK 8-BIT SHIFT REGISTER CS LATCHED ON CS: OUTPUT CONTROL REGISTER (OUT) DOUT MAX4896 Space-Saving, 8-Channel Relay/Load Driver Table 1. Serial-Input Address DIN D0 D1 D2 D3 D4 D5 D6 D7 OUT_ OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 Table 2. Serial-Output Address DIN DO0 DO1 DO2 DO3 DO4 DO5 DO6 DO7 OUT_ OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 Table 3. Status-Register Output Diagnostic OUTPUT STATUS DO_STATUS BIT DIAGNOSTIC Off Low Normal operation. Off High Fault condition. Output open or short circuit. On Low Fault condition. Short circuit to positive load voltage. On High Normal operation. CS tCSW tCL tCSS tCSO tCSH tCH SCLK tDS DIN tDH D7 D6 D0 D1 tDO DOUT tON, tOFF OUT_ Figure 2. 3-Wire Serial-Interface Timing www.maximintegrated.com Maxim Integrated 9 MAX4896 Space-Saving, 8-Channel Relay/Load Driver The minimum fault-filtering time helps mask short-duration fault conditions, such as driving highly capacitive loads. The typical diagnostics software routine works as follows: Write data to the MAX4896 Wait for tD(FAULT) maximum to ensure diagnostics data is ready and valid Write same data to the MAX4896 and read out the diagnostics data from the shift register Use Table 3 to diagnose the output state. To reduce processor overhead, an interrupt-based diagnostics routine is possible. The diagnostics routine will analyze diagnostics data only when the FLAG output triggers an interrupt. Output Short-Circuit/ Current-Limiting Protection The MAX4896 channels (OUT_) are protected against short-circuits conditions. When the channel's output current exceeds the current-limit threshold (ILIM) for longer than the minimum fault-filtering time (tD(FAULT) min), the short-circuit protection is activated. The shortcircuit protection behavior is determined by the logic level at SPLD. When SPLD = high, an overloaded channel remains in a current-limited state until the short-circuit condition is removed or thermal shutdown is reached. This allows the operation of loads where the inrush currents may exceed the MAX4896 internal current limit. When SPLD = low, an overloaded channel immediately turns off (latched-off). When a shorted output is latched off, the channel can be turned back on after the next serial input data is latched into the MAX4896. Open-Load Detection The MAX4896 features an output pulldown current source, along with a voltage comparator, to detect an open-load fault condition. To enable the open-load detection function, PDCD must be low. The voltage at OUT_ is compared with the diagnostics threshold voltage (VDS(OL)) to determine whether a open-load fault condition exists. www.maximintegrated.com Thermal Shutdown If the junction temperature exceeds +160C, all outputs are switched off immediately (no filtering time) and FLAG asserts. The hysteresis is approximately +20C, disabling thermal shutdown once the temperature drops below +140C. RESET The MAX4896 features an asynchronous reset input that allows the user to simultaneously turn all outputs off using a single control line. Drive RESET low to clear all latches and registers, and to turn off all outputs. While RESET is low, the OUT pulldown currents are disabled, regardless of the state of PDCD. FLAG Output FLAG is an open-drain latched output that can be connected to a P interrupt and pulls low whenever a fault condition (short-circuit and/or open-load) is detected in any of the eight outputs for longer than the minimum fault-filtering time (tD(FAULT) min). When not using all channels, connect unused outputs to VS through a 10k pullup resistor to avoid inadvertently triggering the FLAG. FLAG asserts immediately, (no filtering time), when a thermal-shutdown fault condition is detected. The latch FLAG deasserts on CS rising edge. Applications Information Daisy Chaining The MAX4896 features a digital output (DOUT) that provides a simple way to daisy chain multiple devices. This feature allows the user to drive large banks of relays using only a single serial interface. To daisy chain multiple devices, connect all CS inputs together and connect the DOUT of one device to the DIN of another device (see Figure 3). During operation, a stream of serial data is shifted through all the MAX4896s in series. Inductive Kickback Protection Each output features an output protection clamp, limiting the OUT voltage to 65V (typ). The clamp protects against voltage transient when driving inductive loads. Maxim Integrated 10 MAX4896 Space-Saving, 8-Channel Relay/Load Driver VS VS 0.1F 0.1F DEVICE 1 DEVICE 2 VS DIN VS DIN DIN DOUT DOUT MAX4896 MAX4896 OUT1 SCLK SCLK CS OUT1 SCLK OUT8 GND OUT8 PGND GND CS PGND CS Figure 3. Daisy-Chain Configuration Functional Diagram VS PDCD SPLD OUT1 CLAMP RESET GATE CONTROL AND CURRENT LIMITING 8-BIT LATCH OPEN / SHORT DETECT SPI/CONTROL INTERFACE DIN DOUT SCLK CS OVERTEMPERATURE PROTECTION FLAG CHANNEL 1 CHANNEL 2 OUT2 CHANNEL 3 OUT3 CHANNEL 4 OUT4 CHANNEL 5 OUT5 CHANNEL 6 OUT6 CHANNEL 7 OUT7 CHANNEL 8 OUT8 MAX4896 GND www.maximintegrated.com PGND Maxim Integrated 11 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Pin Configuration OUT4 GND OUT5 OUT6 PROCESS: BiCMOS OUT3 TOP VIEW Chip Information 15 14 13 12 11 Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.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. PGND 16 10 PGND OUT2 17 9 OUT7 8 OUT8 7 SPLD PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 6 PDCD 20 TQFN-EP T2055+5 21-0140 90-0010 MAX4896 OUT1 18 VS 19 *EP + 1 2 3 4 5 RESET CS DIN SCLK DOUT FLAG 20 TQFN (5mm x 5mm) *EXPOSED PAD. CONNECT TO PGND. www.maximintegrated.com Maxim Integrated 12 MAX4896 Space-Saving, 8-Channel Relay/Load Driver Revision History REVISION NUMBER REVISION DATE 0 10/05 Initial release 1 6/07 Removal of future product notice 2 12/07 EP clarification 7 3 7/12 Updated FLAG Output section 10 4 5/14 Removed automotive reference under Applications section 1 DESCRIPTION PAGES CHANGED -- - For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated's website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. (c) 2014 Maxim Integrated Products, Inc. 13 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: MAX4896ATP+ MAX4896ATP+T MAX4896ETP+ MAX4896ETP+T