Click here for production status of specific part numbers. Evaluates: MAX17536 MAX17536EVKITA 3.3V Output-Voltage Application Evaluation Kit General Description Quick Start The MAX17536 3.3V output evaluation kit (EV kit) provides Recommended Equipment a proven design to evaluate this high-voltage, high-efficiency, MAX17536EVKITA synchronous step-down DC-DC converter. The EV kit is 4.5V to 60V, 10A DC input power supply preset for a 3.3V output at load currents up to 4A and features a 450kHz switching frequency for optimum efficiency and Load capable of sinking 4A component size. The EV kit features adjustable input, Digital voltmeter (DVM) undervoltage lockout, adjustable soft-start, open-drain RESET signal, and external frequency synchronization. Procedure The EV kit is fully assembled and tested. Follow the steps Features below to verify board operation. Caution: Do not turn Operates from a 4.5V to 60V Input Supply on power supply until all connections are completed. 3.3V Output Voltage 1) Set the power supply at a voltage between 4.5V and 60V. Disable the power supply. Up to 4A Output Current 2) Connect the positive terminal of the power supply to 450kHz Switching Frequency the VIN PCB pad and the negative terminal to the Enable/UVLO Input, Resistor-Programmable UVLO nearest PGND PCB pad. Connect the positive terminal Threshold of the 4A load to the VOUT PCB pad and the negative Adjustable Soft-Start Time terminal to the nearest PGND PCB pad. MODE Pin to Select Among PWM, PFM, or DCM 3) Connect the DVM across the VOUT PCB pad and Modes the nearest PGND PCB pad. Open-Drain RESET Output 4) Verify that shunt is installed across pins 1-2 on jumper JU1 (see Table 1 for details). External Frequency Synchronization 5) Select the shunt position on JU2 based on the Overcurrent and Overtemperature Protection intended mode of operation (see Table 2 for details). Proven PCB Layout 6) Turn on the DC power supply. Fully Assembled and Tested 7) Enable the load. 8) Verify that the DVM displays 3.3V Ordering Information appears at end of data sheet. 19-7690 Rev 2 4/18Evaluates: MAX17536 MAX17536EVKITA Evaluation Kit 3.3V Output-Voltage Application Mode/SYNC Selection (MODE) Detailed Description The devices MODE pin should be used to select among The MAX17536 EV kit provides a proven design to the PWM, PFM, or DCM modes of operation. The logic evaluate the high-voltage, high-efficiency, synchronous state of the MODE pin is latched when the V and step-down DC-DC converter. The EV kit is preset for a CC EN/UVLO voltages exceed the respective UVLO rising 3.3V output from a 4.5V to 60V input at load currents of thresholds and all internal voltages are ready to allow LX up to 4A and features a 450kHz switching frequency for switching. State changes on the MODE pin are ignored optimum efficiency and component size. during normal operation. Refer to the MAX17536 IC data The EV kit includes an EN/UVLO PCB pad and JU1 to sheet for more information on the PWM, PFM, and DCM enable the output at the desired input voltage. The SYNC modes of operation. PCB pad allows an external clock to synchronize the Table 2 shows EV kit jumper settings that can be used to device. JU2 allows the selection of a particular mode of configure the desired mode of operation. operation based on light-load performance requirements. An additional RESET PCB pad is available for monitoring The internal oscillator of the device can be synchronized whether the converter output is in regulation. to an external clock signal on the SYNC pin. The external synchronization clock frequency must be between 1.1f SW Soft-Start Input (SS) and 1.4f , where f is the frequency of operation SW SW The device utilizes an adjustable soft-start function to set by R5. The minimum external clock high pulse width limit inrush current during startup. The soft-start time is should be greater than 50ns and the minimum external adjusted by the value of the external capacitor from SS to clock low pulse width should be greater than 160ns. GND (C7). The selected output capacitance (C ) and SEL output voltage (V ) determine the minimum value of OUT Table 1. Regulator Enable (EN/UVLO) C7, as shown by the following equation: Description (JU1) -6 C7 28 x 10 x C x V SEL OUT SHUNT MAX17536 The soft-start time (t ) is related to C7 by the following EN/UVLO PIN SS POSITION OUTPUT equation: 1-2* Connected to VIN Enabled -6 t = C7/(5.55 x 10 ) SS Connected to the center Enabled, UVLO level For example, to program a 2.2ms soft-start time, C7 Not node of resistor-divider set through the R1 installed should be 12nF. R1 and R2 and R2 resistors Regulator Enable/Undervoltage-Lockout 2-3 Connected to SGND Disabled Level (EN/UVLO) *Default position. The device offers an adjustable-input, undervoltage- lockout level. For normal operation, a shunt should be Table 2. MODE Description (JU2) installed across pins 1-2 on JU1. To disable the output, install a shunt across pins 2-3 on JU1 and pull the EN/ SHUNT MAX17536 MODE PIN POSITION MODE UVLO pin to GND. See Table 1 for JU1 settings. PFM mode of Set the voltage at which the device turns on with the resistive Not installed* Unconnected operation voltage-divider R1/R2 connected from VIN to SGND. Connect the center node of the divider to EN/UVLO. PWM mode of 1-2 Connected to SGND operation Choose R1 to be 3.32M and then calculate R2 as follows: DCM mode of 2-3 Connected to VCC R1x1.215 operation R2 = V 1.215 INU *Default position. where V is the voltage at which the device is required INU to turn on. Maxim Integrated 2 www.maximintegrated.com