MAX17504 3.3V Output Evaluation Kit Evaluates: MAX17504 in 3.3V Output-Voltage Application General Description Features The MAX17504 3.3V output evaluation kit (EV kit) provides Operates from a 5V to 60V Input Supply a proven design to evaluate the MAX17504 high-voltage, 3.3V Output Voltage high-efficiency, synchronous step-down DC-DC convert- Up to 3.5A Output Current er. The EV kit is preset for 3.3V output at load currents 450kHz Switching Frequen cy up to 3.5A and features a 450kHz switching frequency for optimum efficiency and component size. The EV kit Enable / UVLO Input, Resistor-Programmable UVLO features adjustable input undervoltage lockout, adjust- Threshold able soft-start, open-drain RESET signal, and external Adjustable Soft-Start Time frequency synchronization. MODE Pin to Select Among PWM, PFM, or DCM Modes Open-Drain RESET Output Ordering Information appears at end of data sheet. External Frequency Synchronization Overcurrent and Overtemperature Protection Proven PCB Layout Fully Assembled and Tested Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION 2.2F 10%, 100V X7R ceramic 6.8H, 5A inductor C1, C8 2 capacitors (1210) L1 1 Coilcraft MSS1048-682NL Murata GRM32ER72A225KA35 Cooper Bussmann DR125-6R8-R R1 1 3.32M 1% resistor (0402) 2.2F 10%, 10V X7R ceramic C2 1 capacitor (0603) R2 1 750k 1% resistor (0402) Murata GRM188R71A225K R3 1 82.5k 1% resistor (0402) R4 1 30.9k 1% resistor (0402) 12000pF 10%, 16V X7R ceramic C3 1 capacitor (0402) R5 1 45.3k 1% resistor (0402) Murata GRM155R71C123K R6 1 10k 1% resistor (0402) 22F 10%, 10V X7R ceramic TP1, TP2 2 Test pads C4, C9 2 capacitors (1210) Buck converter (20 TQFN-EP*) Murata GRM32ER71A226K U1 1 Maxim MAX17504ATP+ 0.1F 10%, 16V X7R ceramic 3 Shunts (JU1JU3) C5 1 capacitor (0402) PCB: MAX17504 3.3V Output Murata GRM155R71C104K 1 EVKIT Not installed, ceramic capacitor *EP = Exposed pad. C6 0 (0402) Note: C7, R1, and R2 are optional components R1 and R2 47F, 80V aluminum electrolytic are not needed if the EN/UVLO pin is permanently connected C7 1 capacitor (D = 10mm) to VIN. The electrolytic capacitor (C7) is required only when the VIN power supply is situated far from the MAX17504-based Panasonic EEEFK1K470P circuit. When R5 is open, the device switches at 500kHz switch- JU1JU3 3 3-pin headers ing frequency. The MSS1048 inductor has been used to prepare the EV kit test report. 19-6888 Rev 1 2/14MAX17504 3.3V Output Evaluation Kit Evaluates: MAX17504 in 3.3V Output-Voltage Application Component Suppliers SUPPLIER PHONE WEBSITE Coilcraft, Inc. 847-639-6400 www.coilcraft.com Cooper Bussmann 636-394-2877 www.cooperindustries.com Murata Americas 800-241-6574 www.murataamericas.com Panasonic Corp. 800-344-2112 www.panasonic.com Note: Indicate that you are using the MAX17504 when contacting these component suppliers. Quick Start Detailed Description The MAX17504 3.3V output EV kit provides a proven Recommended Equipment design to evaluate the MAX17504 high-voltage, high- MAX17504 3.3V output EV kit efficiency, synchronous step-down DC-DC converter. The 5V to 60V, 7A DC input power supply EV kit is preset for 3.3V output from 5V to 60V input at load currents up to 3.5A and features a 450kHz switching Load capable of sinking 3.5A frequency for optimum efficiency and component size. Digital voltmeter (DVM) The EV kit includes an EN / UVLO PCB pad and jumper Procedure JU1 to enable the output at a desired input voltage. The The EV kit is fully assembled and tested. Follow the steps SYNC PCB pad and jumper JU3 allow an external clock below to verify the board operation. Caution: Do not turn to synchronize the device. Jumper JU2 allows the selec- on power supply until all connections are completed. tion of a particular mode of operation based on light-load performance requirements. An additional RESET PCB 1) Set the power supply at a voltage between 5V and pad is available for monitoring whether the converter out- 60V. Disable the power supply. put is in regulation. 2) Connect the positive terminal of the power supply to the VIN PCB pad and the negative terminal to the Soft-Start Input (SS) nearest PGND PCB pad. Connect the positive termi- The device utilizes an adjustable soft-start function to nal of the 3.5A load to the VOUT PCB pad and the limit inrush current during startup. The soft-start time is negative terminal to the neares t PGND PCB pad. adjusted by the value of C3, the external capacitor from SS to GND. The selected output capacitance (C ) and 3) Conn ect the DVM across the VOUT PCB pad and the SEL nearest PGND PCB pad. the output voltage (V ) determine the minimum value OUT of C3, as shown by the followin g equation: 4) Verify that shunts are installed across pins 1-2 on -6 C3 28 x 10 x C x V jumper JU1 and pins 2-3 on jumper JU3 (see Tables 1 SEL OUT and 3 for details). The soft-start time (t ) is related to C3 by the following SS equation: 5) Select the shunt position on jumper JU2 according to the intended mode of operation (see Table 2 for -6 t = C3/(5.55 x 10 ) SS details). For example, to program a 2.2mS soft-start time, C3 6) Turn on the DC power supply. should be 12nF. 7) Enable the load. 8) Verify that the DVM displays 3.3V. Maxim Integrated 2 www.maximintegrated.com