Click here to ask about the production status of specific part numbers. Evaluates: MAX25231 MAX25231 Evaluation Kit Procedure General Description The EV kit is fully assembled and tested, follow the steps The MAX25231 evaluation kit (EV kit) provides a proven below to activate the board. Caution: Do not turn on the design to evaluate the MAX25231 2.1MHz high-voltage power supply until all connections are completed. mini-buck converters in a 12-pin TDFN package. All com- ponents are rated for the automotive temperature range. 1) Verify that all jumpers are in their default positions, as Various test points and jumpers are included for evaluation. shown in Table 1. 2) Connect the positive and negative terminals of The EV kit comes with a MAX25231ATCA/V+ installed, but the power supply to the SUP and GND test pads, can also be used to evaluate all other MAX25231 variants respectively. with minimal U1 component changes. 3) Connect the positive terminal of the voltmeter to OUT, and the negative terminal to GND2. Features 4) Set the power supply to 14V and 2A current limit. Turn 3.5V to 36V Input Supply Range on the power supply. 5V or 3.3V Fixed Output Voltage, or Adjustable 5) With the PU and LED jumpers shorted, the green Between 1V and 10V LED should light up. The voltmeter should display Delivers Up to 1.2A Output Current an output voltage of 5V. Frequency-Synchronization Input Additional Evaluation Enable Input 6) Connect the positive and negative terminals of an electronic load to OUT and GND, respectively. Voltage-Monitoring PGOOD Output 7) Set the electronic load to 100mA or use an equivalent Proven PCB Layout resistive load. The resistive load is calculated based Fully Assembled and Tested on 5V output and should be approximately 50. If using a resistor load, make sure it can handle 0.5W. Quick Start 8) Turn on the power supply and electronic load. Verify Required Equipment that OUT is 5V. MAX25231 EV kit 3.5V to 36V, 2A power supply Voltmeter Table 1. Default Jumper Settings Electronic load SHUNT JUMPER FUNCTION POSITION EN Middle-ON Buck controller enabled SPS Middle-OFF Spread spectrum disabled PGOOD pulls up to V BIAS PU, LED Installed when OUT is in regulation SYNC Middle-FPWM Forced-PWM mode Ordering Information appears at end of data sheet. 319-100645 Rev 0 11/20Evaluates: MAX25231 MAX25231 Evaluation Kit Evaluating the Other Variants Detailed Description The device is available in fixed 5V and 3.3V outputs. The EV The MAX25231 EV kit provides a proven layout for the kit comes installed with the 5V output version. MAX25231 2.1MHz synchronous buck regulator. The device accepts input voltages as high as 36V and deliv- Setting the Output Voltage in ers up to 1.2A. The EV kit can handle an input-supply Buck Converters transient up to 42V. Various test points are included for To externally adjust the output voltage (OUT) between 3V evaluation. and 10V, remove R1 and install a 0 resistor on R4. Place Switching Frequency/ appropriate resistors in positions R5 and R6 according to External Synchronization the following equation: The device can operate in two modes: forced-PWM V OUT or skip. Skip mode has better efficiency for light-load R5 R6 1 V conditions. When SYNC is pulled low, the device operates FB in skip mode for light loads and in PWM mode for larger where V = 1V (typ). FB loads. When SYNC is pulled high, the device is forced to operate in PWM across all load conditions. SYNC can be used to synchronize with other supplies if a Ordering Information clock source is present. The device is forced to operate in PWM when SYNC is connected to a clock source. PART TYPE MAX25231EVKIT EV Kit Buck Output Monitoring (PGOOD) The EV kit provides a power-good output test point Denotes RoHS compliance. (PGOOD) to monitor the status of the buck output (OUT). PGOOD is low impedance when the output voltage is in regulation. PGOOD is high impedance when the output voltage drops below 6.5% (typ) of its nominal regulated voltage. To obtain a logic signal, pull up PGOOD to V by BIAS installing shunts on jumpers PU and LED. Maxim Integrated 2 www.maximintegrated.com =