Evaluates: MAX17545 in MAX17545 5V Output Evaluation Kit 5V Output-Voltage Application General Description Features The MAX17545 5V output evaluation kit (EV kit) provides Operates from a 6.5V to 42V Input Supply a proven design to evaluate the MAX17545 high-voltage, 5V Output Voltage high-efficiency, synchronous step-down DC-DC convert- Up to 1.7A Output Current er. The EV kit is preset for 5V output at load currents up 500kHz Switching Frequency to 1.7A and features a 500kHz 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 Ordering Information appears at end of data sheet. Open-Drain RESET Output 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%, 50V X7R ceramic 10 H inductor C1 1 capacitor (1210) L1 1 Coilcraft XAL6060-103ME TDK C3225X7R1H225K Cooper Bussmann MPI4040R4-100-R R1 1 3.32M 1% resistor (0402) 2.2F 10%, 10V X7R ceramic C2 1 capacitor (0603) R2 1 732k 1% resistor (0402) Murata GRM188R71A225K R3 1 178k 1% resistor (0402) 5600pF 10%, 25V X7R ceramic R4 1 39k 1% resistor (0402) C3 1 capacitor (0402) R5 0 Not installed, resistor (0402) Murata GRM155R71E562K R6 1 10k 1% resistor (0402) 22F 10%, 10V X7R ceramic TP1, TP2 2 Test pads C4 1 capacitor (1210) Buck converter (20 TQFN-EP*) Murata GRM32ER71A226K U1 1 Maxim MAX17545ATP+ 0.1F 10%, 16V X7R ceramic 3 Shunts (JU1JU3) C5 1 capacitor (0402) 1 PCB: MAX17545 5V OUTPUT EVKIT Murata GRM155R71C104K *EP = Exposed pad. Not installed, ceramic capacitor C6 0 (0402) Note: C7, R1, and R2 are optional components R1 and R2 are not needed if the EN/UVLO pin is permanently connected to 47F, 50V aluminum electrolytic VIN. The electrolytic capacitor (C7) is required only when the C7 1 capacitor (D = 10mm) VIN power supply is situated far from the MAX17545-based Panasonic EEEFK1H470XP circuit. When R5 is open, the device switches at 500kHz switching frequency. The XAL6060 inductor has been used to JU1JU3 3 3-pin headers prepare the EV kit test report. 19-7352 Rev 0 10/14Evaluates: MAX17545 in MAX17545 5V Output Evaluation Kit 5V Output-Voltage Application Component Suppliers SUPPLIER PHONE WEBSITE Coilcraft, Inc. 847-639-6400 www.coilcraft.com CooperBussmann 713-209-8400 www.cooperindustries.com Murata Americas 800-241-6574 www.murataamericas.com Panasonic Corp. 800-344-2112 www.panasonic.com TDK Corp. 516-535-2600 www.tdk.com Note: Indicate that you are using the MAX17545 when contacting these component suppliers. Quick Start Detailed Description The MAX17545 5V output EV kit provides a proven Recommended Equipment design to evaluate the MAX17545 high-voltage, high- MAX17545 5V output EV kit efficiency, synchronous step-down DC-DC converter. The 6.5V to 42V, 4A DC input power supply EV kit is preset for 5V output from 6.5V to 42V input at load currents up to 1.7A and features a 500kHz switching Load capable of sinking 2A 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 6.5V and pad is available for monitoring whether the converter out- 42V. 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 terminal The device utilizes an adjustable soft-start function to of the 1.7A load to the VOUT PCB pad and the nega- limit inrush current during startup. The soft-start time is tive terminal to the nearest PGND PCB pad. adjusted by the value of C3, the external capacitor from SS to GND. The selected output capacitance (C ) and 3) Connect 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 following 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 Table 1 SEL OUT and Table 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 1ms soft-start time, C3 should 6) Turn on the DC power supply. be 5.6nF. 7) Enable the load. 8) Verify that the DVM displays 5V. Maxim Integrated 2 www.maximintegrated.com