Click here for production status of specific part numbers. Evaluates: MAX17557 5V MAX17557EVKIT Evaluation Kit Output-Voltage Application General Description Quick Start The MAX17557 5V-output evaluation kit (EV kit) provides Recommended Equipment a proven design to evaluate the MAX17557 high-voltage, MAX17557 5V-output EV kit high-efficiency, synchronous step-down DC-DC controller. 6.5V to 60V, 10A DC-input power supply The EV kit provides 5V/10A at the output from a 6.5V to 60V input supply. The switching frequency of the EV kit is Load capable of sinking 10A preset to 350kHz for optimum efficiency and component Digital voltmeter (DVM) size. The EV kit features Enable/UVLO Input, selectable PWM/DCM modes, resistor-programmable UVLO thresh- Procedure old, adjustable soft-start time, open-drain PGOOD output, The EV kit is fully assembled and tested. Follow the steps and overcurrent and overtemperature protection. below to verify the board operation. Caution: Do not turn on power supply until all connections are completed. Features 1) Set the power supply at a voltage between 6.5V and Operates from a 6.5V to 60V Input Supply 60V. Disable the power supply. 5V Output Voltage 2) Connect the positive terminal of the power supply to the V PCB pad and the negative terminal to the IN Up to 10A Output Current nearest PGND PCB pad. Connect the positive ter- 350kHz Switching Frequency minal of the 10A load to the V PCB pad and the OUT Enable/UVLO Input, Resistor-Programmable UVLO negative terminal to the nearest PGND PCB pad. Threshold 3) Connect the DVM across the V PCB pad and OUT the nearest PGND PCB pad. Selectable PWM/DCM Modes of Operation 4) Place the shunt on the jumpers JU1, JU2, JU3, and Adjustable Soft-Start Time JU4 according to the intended operation (see Tables 1, Programmable Soft-Stop Enable or Disable Function 2, 3, and 4 for details). 5) Turn on the DC power supply. Open-Drain PGOOD Output 6) Enable the load. Overcurrent (OCP) and Overtemperature (OTP) 7) Verify that the DVM displays 5V. Protection Proven PCB Layout Fully Assembled and Tested Ordering Information appears at end of data sheet. 319-100068 Rev 1 3/18Evaluates: MAX17557 5V MAX17557EVKIT Evaluation Kit Output-Voltage Application Setting the Input Undervoltage Lockout Level Detailed Description of Hardware The EN pin can be open or pulled up to a voltage between The MAX17557 5V-output evaluation kit (EV kit) is a 1.25V and 5.5V to turn on the controller. Figure 1 shows the proven design to evaluate the MAX17557 high-voltage, possible configurations. The EN pin can be used as input high-efficiency, synchronous step-down DC-DC control - undervoltage lockout detector with a typical hysteresis of ler. The EV kit provides 5V/10A at the output from a 6.5V 100mV. As shown in Figure 1, the input voltage at which to 60V input supply. The switching frequency of the EV the controller of the IC turns on, can be set with a resistor- kit is preset to 350kHz for optimum efficiency and com - divider connected to EN from IN to GND. Select R2 = 10k ponent size. The EV kit features current sensing using and calculate R1 based on the following equation: either an external current-sense resistor for accuracy or an inductor DCR for improved system efficiency. Current (V 1.25) IN UVLO foldback limits MOSFET power dissipation under short- R1 R2 1.25 circuit conditions. The MODE/SYNC PCB pad allows an external clock to synchronize the device. Jumper JU1 where V is the input voltage at which the controller INUVLO allows the selection of the mode of operation based on should be enabled. light load-performance requirements. The EV kit includes See Table 3 for JU3 jumper settings and descriptions of an EN PCB pad and jumper JU3 to enable the output at controller enable/undervoltage lockout (EN). a desired input voltage. A PGOOD PCB pad is available for monitoring when the converter output is in regulation. V TO V IN MIN IN MAX IN 4.5V TO 60V IN R1 MAX17557 MAX17557 EN R2 EN ALWAYS-ON CONFIGURATION ENABLE AS INPUT UVLO VIN MAX / VIN MIN 4.4 V TO V IN MIN IN MAX 4.5V TO 60V IN IN R1 MAX17557 MAX17557 EN >1.25V R2 D1 4.7V EN TURN ON/OFF BY ENABLE AS INPUT UVLO LOGIC SIGNAL V / V 4.4 IN MAX IN MIN Figure 1. Setting the Input Under Voltage Lockout Maxim Integrated 2 www.maximintegrated.com =