Click here for production status of specific part numbers. Evaluates: MAX25612 MAX25612 Evaluation Kit General Description Quick Start The MAX25612 evaluation kit (EV kit) provides a proven Required Equipment design to evaluate the MAX25612 automotive high- MAX25612 EV kit voltage, high-brightness LED (HB LED) synchronous 12V, 5A DC power supply controller. The EV kit is set up for boost and buck-boost configurations and operates from a 6V-to-18V DC supply A series-connected LED string rated at 2A voltage. The EV kit is configured to deliver up to 2A to one Oscilloscope with a current probe string of LEDs. The total voltage of the string can vary from 3V to 48V. Procedure The EV kit is fully assembled and tested. Follow the steps Features below to verify board operation. Caution: Do not turn on Configured for Boost or Buck-Boost Mode the power supply until all connections are made. Synchronous Controller and Power Stage 1) Verify that all jumpers (J1-J2) are in their default positions, as shown in Table 1. Analog Dimming Control 2) Connect the positive terminal of the 12V supply to Analog or Digital PWM Dimming the IN PCB pad or the red banana plug receptacle. 3) Connect the negative terminal of the 12V supply to the GND PCB pad or the black banana plug recep- tacle. 4) Connect the LED string across the LED+ and LED- PCB pads on the EV kit for buck-boost configura - tion. For boost configuration, connect the LED string across the LED+ and GND PCB pads on the EV kit. The LED string voltage should be higher than the Ordering Information appears at end of data sheet. input voltage in this configuration. 5) Clip the current probe on the wire connected to the LED string. 6) Turn on the DC power supply. 7) Verify that the LEDs turn on. 8) Verify that the oscilloscope displays approximately 2A. 319-100436 Rev 0 9/19Evaluates: MAX25612 MAX25612 Evaluation Kit Pulse-Dimming Input (PWMDIM) Detailed Description When a shunt is installed across pins 1-2 of J1, the PWM The MAX25612 EV kit provides a proven design to evalu- duty cycle is set by the R13/R18 resistor-divider. In this ate the MAX25612 synchronous high-voltage HB LED mode of operation, an analog voltage between 0.2V and driver with integrated high-side current sense. The EV 3V generates an LED pulse duty cycle between 0% and kit is set up for boost and buck-boost configurations and 100%, respectively. The frequency of this LED pulse mod- operates from a 6V-to-18V DC supply voltage. The EV kit ulation is 200Hz, which is generated internally from the is configured to deliver up to 2A to a series LED string. MAX25612 device. When a shunt is installed across pins The string forward voltage can vary from 3V to 48V. 2-3 of J1, the PWMDIM input of the device is grounded Analog Dimming Control (ICTRL) and the LEDs are off. When a shunt is installed across pins 1-2 of J2, the LED Alternatively, an external signal (either analog or digital current is set by the R1/R2 resistor-divider. The LED cur- PWM) can be applied directly across the PWMDIM test rent is linearly proportional to the voltage on the ICTRL point and the SGND pad to control the LEDs. The J1 input. An ICTRL voltage of 200mV or less corresponds to jumper should be left open when using an external source I = 0A. An ICTRL voltage of 1.3V or more corresponds LED attached to the PWMDIM test point. to I = 2.2A. Between 200mV and 1.3V, the LED current LED is linearly adjusted between 0A and 2.2A, respectively. To set the LED current with an external reference, remove the shunt installed across J2, and apply a voltage across the ICTRL test point and the SGND pad. Table 1. Table Title here SHUNT JUMPER DESCRIPTION POSITION Analog voltage on the PWMDIM input of the device is controlled by the voltage divider 1-2* of R13 and R18. Adjust R18 to vary the analog voltage on PWMDIM, which varies the LED pulse width using the internal 200Hz dimming signal. J1 2-3 PWMDIM input of the device is connected to ground. LEDs are off. PWMDIM input of the device is disconnected from the voltage divider. Apply a digital Open PWM signal across the PWMDIM test point and the SGND pad to control the LEDs. ICTRL pin is now connected to a voltage-divider from V to ground. Adjusting R2 CC 1-2* allows programming the LED current from 0 to 2.2A. J2 Disconnects the ICTRL pin of the device from the external voltage divider on the V CC Open pin. Allows the user to apply an external voltage across the ICTRL test point and the SGND pad to set the LED current level. *Default position. Ordering Information PART TYPE MAX25612EVKIT EV Kit Denotes RoHS compliant. Maxim Integrated 2 www.maximintegrated.com