Click here for production status of specific part numbers. Evaluates: MAX17504 in MAX17504EVKITBE Evaluation Kit 5V Output-Voltage Application General Description Quick Start The MAX17504EVKITBE evaluation kit (EV kit) provides Recommended Equipment a proven design to evaluate the MAX17504 high-voltage, MAX17504EVKITBE high-efficiency, synchronous step-down DC-DC convert- 7.5V to 60V, 5A DC input power supply er. The EV kit is preset for 5V output at load currents up to 3.5A and features a 500kHz switching frequency for Load capable of sinking 3.5A optimum efficiency and component size. The EV kit Digital voltmeter (DVM) features adjustable input undervoltage lockout, adjustable soft-start, open-drain RESET signal, and external clock Equipment Setup and Test Procedure synchronization. The EV kit also provides a good layout The EV kit is fully assembled and tested. Follow the steps example, which is optimized for conducted, radiated EMI, below to verify the board operation. and thermal performance. For more details about the IC Caution: Do not turn on power supply until all con- benefits and features, refer to the MAX17504 data sheet. nections are completed. 1) Set the power supply at a voltage between 7.5V and Features 60V. Disable the power supply. Operates from a 7.5V to 60V Input Supply 2) Connect the positive terminal of the power supply to Programmed 5V Output Voltage, 3.5A Load Current the VIN PCB pad and the negative terminal to the 500kHz Switching Frequency nearest PGND PCB pad. Connect the positive terminal Enable/UVLO Input, Resistor-Programmable UVLO of the 3.5A load to the VOUT PCB pad and the nega- Threshold tive terminal to the nearest PGND PCB pad. Adjustable Soft-Start Time 3) Connect the DVM across the VOUT PCB pad and the nearest PGND PCB pad. MODE Pin to Select Among PWM, PFM, or DCM Modes 4) Verify that shunts are installed across pins 1-2 on jumper JU1 and pins 2-3 on jumper JU3 (see Table 1 Open-Drain RESET Output and Table 3 for details). External Clock Synchronization 5) Select the shunt position on jumper JU2 according Overcurrent and Overtemperature Protection to the intended mode of operation (see Table 2 for Proven PCB Layout details). Fully Assembled and Tested 6) Turn on the DC power supply. Complies with CISPR22(EN55022) Class B 7) Enable the load. Conducted and Radiated Emissions 8) Verify that the DVM displays 5V. Ordering Information appears at end of data sheet. 319-100342 Rev 0 4/19Evaluates: MAX17504 in MAX17504EVKITBE Evaluation Kit 5V Output-Voltage Application Choose R1 to be 3.32M (max), and then calculate R2 Detailed Description as follows: The MAX17504EVKITBE provides a proven design to evaluate the MAX17504 high-voltage, high-efficiency, R 1.215 1 synchronous step-down DC-DC converter. The EV kit R = 2 (V 1.215) INU is preset for 5V output from 7.5V to 60V input at load currents up to 3.5A and features a 500kHz switching where, V is the voltage at which the device is required INU frequency for optimum efficiency and component size. to turn on, and R1 and R2 are in k, The EV kit includes an EN/UVLO PCB pad and jumper For more details about setting the undervoltage lockout JU1 to enable the output at a desired input voltage. The Level, refer to the MAX17504 data sheet. SYNC PCB pad and jumper JU3 allow an external clock MODE Selection (MODE) to synchronize the device. Jumper JU2 allows the selec- tion of a particular mode of operation based on light-load The EV kit provides a jumper (JU2) that allows the MAX17504 to operate in PWM, PFM, and DCM modes. performance requirements. An additional RESET PCB pad is available for monitoring whether the converter out- Refer to the MAX17504 data sheet for more details on the modes of operation. put is in regulation. Table 2 shows the mode selection (JU2) settings that can Soft-Start Input (SS) be used to configure the desired mode of operation. The EV kit offers an adjustable soft-start function to limit inrush current during startup. The soft-start time Table 1. Converter EN/UVLO Jumper is adjusted by the value of external soft-start capacitor (C10) connected between SS and SGND. The selected (JU1) Settings output capacitance (C ) and the output voltage (V ) SEL OUT SHUNT determine the minimum value of C10, as shown by the EN/UVLO PIN MAX17504 OUTPUT POSITION following equation: -6 C10 28 x 10 x C x V 1-2* Connected to VIN Enabled SEL OUT The soft-start time (t ) is related to C10 by the following SS Connected to the Enabled, UVLO level equation: Not center node of set through the R1 and -6 t = C10/(5.55 x 10 ) installed resistor-divider R1 SS R2 resistors and R2 For example, to program a 2.2mS soft-start time, C3 should be 12nF. 2-3 Connected to SGND Disabled Enable/Undervoltage-Lockout (EN/UVLO) *Default position Programming The MAX17504 offers an Enable and adjustable input Table 2. Mode Selection (JU2) Settings undervoltage lockout feature. In this EV kit, for normal SHUNT operation, leave the EN/UVLO jumper (JU1) open. When MODE PIN MAX17504 MODE POSITION JU1 is left open, the MAX17504 is enabled when the input voltage rises above 6.4V. To disable the MAX17504, PFM mode of Not installed* Unconnected install a jumper across pins 23 on JU1. See Table 1 operation for JU1 settings. The EN/UVLO PCB pad on the EV Kit Connected to PWM mode of 2-3 supports external Enable/Disable control of the device. SGND operation Leave JU1 open when external Enable/Disable control is Connected to DCM mode of desired. A potential divider formed by R1 and R2 sets the 1-2 VCC operation input voltage (V ) above which the converter is enabled INU when JU1 is left open. *Default position Maxim Integrated 2 www.maximintegrated.com