Evaluates: MAXM17504 in 5V MAXM17504 5V Output Output-Voltage Application Evaluation Kit General Description Features The MAXM17504 evaluation kit (EV kit) is a demonstration Highly Integrated Solution with Integrated Shield circuit of the MAXM17504 high-voltage, high-efficien - Inductor cy, current-mode scheme, synchronous step-down Wide 11V to 60V Input Range DC-DC switching power module. The MAXM17504 Preset 5V Output with a Fixed Resistor-Divider on EV kit is designed for 5V output and delivers up to Feedback Pin (FB) 3.5A load current from a wide input voltage range of 11V to 60V. The EV kit switches at an optimal 500kHz Programmable Output Voltage Feature (0.9V to 12V) switching frequency to allow the use of small component Up to 3.5A Output Current sizes that help minimize solution size while maintaining High 92.5% Efficiency (V = 12V, V = 5V at 1.0A) IN OUT high performance. The EV kit provides a precision- 500kHz Switching Frequency enable input, an open-drain RESET output signal, and external frequency synchronization to provide a simple and Enable/UVLO Input, Resistor-Programmable UVLO reliable startup sequence and eliminate beat frequency Threshold between regulators. The EV kit also includes option- Adjustable Soft-Start Time al component footprints to program different output Selectable PWM, PFM, or DCM Mode voltages, an adjustable input undervoltage-lockout, and a soft-start time to control inrush current during startup. The Open-Drain RESET Output MAXM17504 data sheet provides a complete description External Frequency Synchronization of the part that should be read in conjunction with this Overcurrent and Overtemperature Protection evaluation kit data sheet prior to modifying the demo circuit. Low-Profile, Surface-Mount Components Lead(Pb)-Free and RoHS Compliant Fully Assembled and Tested Ordering Information appears at end of data sheet. 19-7590 Rev 0 4/15Evaluates: MAXM17504 in 5V MAXM17504 5V Output Evaluation Kit Output-Voltage Application also available for monitoring output-voltage regulation to Quick Start enable/disable the application circuit of the load. Recommended Equipment Soft-Start Input (SS) MAXM17504 evaluation kit The device utilizes an adjustable soft-start function to 11V to 60V DC power supply (V ) IN limit inrush current during startup. The soft-start time is Dummy load capable of sinking 3.5A programmed by the value of C1, the external capacitor from SS to GND. The selected output capacitance (C ) Digital voltmeter (DVM) SEL and the output voltage (V ) determine the minimum OUT 100MHz dual-trace oscilloscope value of C1, as shown by the following equation: Procedure 3 C128 10 C V SEL OUT The MAXM17504 EV kit is fully assembled and tested. Please follow the steps below to verify board operation. where C1 is in nF and C is in F. SEL Caution: Do not turn on the power supply until all The soft-start time (t ) is calculated by the equation below: SS connections are completed. 1) Set the power supply at a voltage between 11V and t = C1/ 5.55 SS 60V. Disable the power supply. where t is in ms and C1 is in nF. SS 2) Connect the positive and negative terminals of the power supply to IN and PGND PCB pads, respectively. Programmable Undervoltage-Lockout (UVLO) 3) Connect the positive and negative terminals of the The EV kit offers an adjustable input undervoltage-lockout 3.5A load to OUT and PGND2 PCB pads, respectively, level by resistor-dividers connecting between the IN, EN/ and set the load to 0A. UVLO, and GND pins. For normal operation, a shunt should not be installed across pins 1-2 on JU1 to enable 4) Connect the DVM across the OUT PCB pad and the the output through an internal pullup 3.3M resistor from PGND2 PCB pad. EN/UVLO pin to IN pin. To disable the output, install the 5) Verify that no shunts are installed across pins 1-2 on shunt across pins 1-2 on JU1 to pull the EN/UVLO pin jumper JU1 to enable UVLO (see Table 1 for details). to GND. See Table 1 for JU1 setting details. The EV kit 6) Verify that a shunt is installed across JU3 to disable also provides an optional R3 PCB footprint to program a the external synchronization (see Table 3 for details). UVLO threshold voltage at which an input voltage level device turns on. The R3 resistor can be calculated by the 7) Verify that a shunt is installed across JU2 to enable PWM mode (see Table 2 for details). following equation: 8) Enable the input power supply. 4009.5 R3 = 9) Verify the DVM display 5V. (V 1.215) INU 10) Increase the load up to 3.5A to verify the DVM where V is the input voltage at which the device is continue displaying 5V. INU required to turn on, and R3 unit is in k. Detailed Description of Hardware The MAXM17504 EV kit is a proven circuit to demonstrate the high-voltage, high-efficiency, and compact solution Table 1. UVLO Enable/Disable size of the synchronous step-down DC-DC power mod- Configuration (JU1) ule. The output voltage is preset to 5V to operate from 11V to 60V and provides up to 3.5A load current. The SHUNT MAXM17504 EN PIN optimal frequency is set at 500kHz to maximize POSITION OUTPUT efficiency and minimize component size. The EV kit includes Installed Connected to GND Disable jumper JU1 to enable/disable UVLO of the device, JU2 to Not installed* Connected to VIN Enable configure in PWM, PFM, or DCM mode in advance of *Default position. light-load efficiency, and JU3 to enable/disable external clock synchronize (SYNC). The RESET PCB pad is Maxim Integrated 2 www.maximintegrated.com