Click here for production status of specific part numbers. Evaluates: MAX17682 for Isolated +12V MAX17682EVKIT Evaluation Kit Output Configuration General Description Quick Start The MAX17682 EV kit is a fully assembled and tested Recommended Equipment circuit board that demonstrates the performance of the One 15V - 60V DC, 1A Power Supply MAX17682 high-efficiency, iso-buck DC-DC Converter. One resistive load 750mA sink capacity The EV kit operates over a wide input-voltage range of 16V to 42V and uses primary-side feedback to regulate Two Digital Multimeters (DMM) the output voltage. The EV kit has isolated output, Caution: Do not turn on the power supply until all programmed to +12V at 750mA, with 10% output voltage connections are completed. regulation. Procedure The EV kit comes installed with the MAX17682 in a 20-pin The EV kit comes with the default secondary output (4mm x 4mm) TDFN package. programmed to +12V. Features 1) Verify that J1 is open 16V to 42V Input Voltage Range 2) Set the power supply output to 24V. Disable the power supply +12V, 750mA Continuous Current 3) Connect the positive terminal of the power supply to EN/UVLO Input the VIN PCB pad and the negative terminal to the 200kHz Switching Frequency nearest PGND PCB pad. Connect a 750mA resistive load across the +12V PCB pad and the 91% Peak Efficiency GND0 PCB pad. Overcurrent Protection 4) Connect a DMM configured in voltmeter mode No Optocoupler across the +12V PCB pad and the nearest GND0 PCB pad. Delivers up to 10W Output Power 5) Enable the input power supply. Overtemperature Protection 6) Verify that output voltage is at +12V (with allowable Proven PCB layout tolerance of 10%) with respect to GND0. 7) If required, vary the input voltage from 16V to 42V, and the load current from 0mA to 750mA and verify that output voltage is at +12V (with allowable tolerance Ordering Information appears at end of data sheet. of 10%). 319-100002 Rev 1 4/18Evaluates: MAX17682 for Isolated +12V MAX17682EVKIT Evaluation Kit Output Configuration The iso-buck is a synchronous-buck-converter-based Detailed Description topology, useful for generating isolated outputs at low The MAX17682EVKITA evaluation kit (EV kit) is a fully power level without using an opto-coupler. The detailed assembled and tested circuit board that demonstrates procedure for setting the soft-start time, ENABLE/UVLO the performance of the MAX17682 high-efficiency, iso- divider, primary output voltage (V ) selection, adjusting PRI buck, DC-DC converter designed to provide an isolated the primary output voltage, primary inductance selection, power up to 10W. The EV kit generates +12V, 750mA turns-ratio selection, output capacitor selection, output voltages from a 16V to 42V input supply. The EV kit diode selection and external loop compensation are given features a forced-PWM control scheme that provides in MAX17682 IC data sheet. constant switching-frequency of 200 kHz operation at all load and line conditions. Enable Control (J1) The EV Kit includes an EN/UVLO PCB pad to monitor The EN/UVLO pin on the device serves as an on/ and program the EN/UVLO pin of the MAX17682. The off control while also allowing the user to program the VPRI PCB pad helps measure the regulated primary input undervoltage lockout (UVLO) threshold. Jumper J1 output voltage (V ). An additional RESETB PCB pad configures the EV kits output for turn-on/turn-off control. PRI is available for monitoring the health of primary output Install a shunt across jumper J1 pins 2-3 to disable VOUT. voltage (V ). RESETB pulls low if FB voltage drops See Table 1 for proper J1 jumper configurations. PRI below 92%(typ) of its set value and RESETB goes high impedance 1024 clock cycles after FB voltage rises above 95% of its set value. The programmable soft-start feature allows users to reduce the input inrush current. Table 1. Enable Control (EN/UVLO) (J1) Jumper Settings SHUNT POSITION EN/UVLO PIN V OUTPUT OUT J1 1-2 Connected to V Always Enabled IN 2-3 Connected to GND Always Disabled Open* Connected to midpoint of R1, R2 resistor-divider Enabled at V 15V IN *Default position. Note 1: The secondary output diodes D1 is rated to carry short-circuit current only for few hundredths of a millisecond and is not rated to carry the continuous short-circuit current. Note 2: The iso-buck converter typically needs 10% minimum load to regulate the output voltage. In this design when the +12V rail is healthy, U2 sinks the minimum load current required to regulate the output voltages within 10% regulation. Maxim Integrated 2 www.maximintegrated.com