Evaluates: MAX17632 MAX17632C Evaluation Kit 5V Output-Voltage Application General Description Quick Start The MAX17632C 5V output evaluation kit (EV kit) pro- Recommended Equipment vides a proven design to evaluate the MAX17632C high- MAX17632C 5V output EV kit efficiency, synchronous step-down DC-DC converter. The 6.5V to 36V, 2A DC-input power supply EV kit provides 5V/2A at the output from a 6.5V to 36V input supply. The switching frequency of the EV kit is Load capable of sinking 2A preset to 400kHz for optimum efficiency and component Digital voltmeter (DVM) size. The EV kit features adjustable input undervoltage lockout, adjustable soft-start, open-drain RESET signal, Procedure and external frequency synchronization. The EV kit is fully assembled and tested. Follow the steps below to verify the board operation. Caution: Do not turn Features on power supply until all connections are completed. Operates from a 6.5V to 36V Input Supply 1) Set the power supply at a voltage between 6.5V and 5V Output Voltage 36V. Then, disable the power supply. Delivers Up to 2A Output Current 2) Connect the positive terminal of the power supply to the VIN PCB pad and the negative terminal to the 400kHz Switching Frequency nearest PGND PCB pad. Connect the positive ter- Enable/UVLO Input, Resistor-Programmable UVLO minal of the 2A load to the VOUT PCB pad and the Threshold negative terminal to the nearest PGND PCB pad. Adjustable Soft-Start Time 3) Connect the DVM across the VOUT PCB pad and Open-Drain RESET Output the nearest PGND PCB pad. Overcurrent and Overtemperature Protection 4) Verify that shunts are installed across pins 1-2 on jumper JU1 (see Table 1 for details) and pins 2-3 on Proven PCB Layout jumper JU2 (see Table 2 for details) Fully Assembled and Tested 5) Turn on the DC power supply. 6) Enable the load. 7) Verify that the DVM displays 5V. Ordering Information appears at end of data sheet. 319-100098 Rev 0 11/17Evaluates: MAX17632 MAX17632C Evaluation Kit 5V Output-Voltage Application For example, in order to program a 1ms soft-start time, C3 Detailed Description of Hardware should be 5600pF. The EV kit is designed to deliver 5V at load current up to 2A at the output from a 6.5V to 36V input supply. The Setting the Input Undervoltage Lockout switching frequency of the EV kit is configured at 400 kHz Level (EN/UVLO) by leaving RT resistor open. The device offers an adjustable input undervoltage-lockout The EV kit includes an EN/UVLO PCB pad and jumper level, where output is enabled at the minimum desired JU1 to enable the output at a desired input voltage. The input-voltage level. For always-enable operation, a shunt MODE/SYNC PCB pad and jumper JU2 allow an external should be installed across pins 1-2 on jumper JU1, which clock to synchronize the device. Jumper JU2 allows the pulls up the EN/UVLO to V . In order to disable the output, IN selection of the mode of operation based on light load- install a shunt across pins 2-3 on JU1, which pulls down performance requirements. An additional RESET PCB the EN/UVLO pin to V . See Table 1 for JU1 settings. SGND pad is available for monitoring whether the converter Set the input voltage level (input undervoltage-lockout output is in regulation or not. level) at which the device turns on with the resistive voltage-divider R1 and R2 connected between VIN and Soft-Start Input (SS) SGND. The device utilizes an adjustable soft-start function to Choose R1 to be 3.32M and then calculate R2 as follows: limit inrush current during the startup. The soft-start time is adjusted by the value of C3, the external capacitor from R1 1.215 SS to SGND. The selected output capacitance (C ) SEL R2 = V 1.215 ( ) and the output voltage (V ) determine the minimum INU OUT value of C3, as shown by the following equation: where V is the input voltage at that the device requires INU -6 C3 28 x 10 x C x V SEL OUT to turn on. The soft-start time (t ) is related to the soft-start capaci- SS tor C3 by the following equation: C3 t = SS -6 5.55 10 ) ( Table 1. Regulator Enable (EN/UVLO) Description (JU1) SHUNT POSITION EN/UVLO PIN MAX17632C OUTPUT 1-2* Connected to VIN Enabled Connected to the center node of Enabled, UVLO level is set by the Not installed resistor-divider R1 and R2 resistor-divider between VIN and SGND 2-3 Connected to SGND Disabled *Default position. Maxim Integrated 2 www.maximintegrated.com