BD9A400MUV-EVK-001 ROHM

Switching Regulator Series Step-Down DC/DC Converter BD9A400MUV Evaluation Board BD9A400MUV-EVK-001 Description This evaluation board has been developed for ROHMs synchronous buck DC/DC converter customers evaluating BD9A400MUV. While accepting a power supply of 2.7-5.5V, an output of 1.8V can be produced. The IC has internal 60m high-side N-channel MOSFET and 60m low-side N-channel MOSFET and a synchronization frequency is of 1MHz. A Soft Start circuit prevents in-rush current during startup. An EN pin allows for simple ON/OFF control of the IC to reduce standby current consumption. A MODE pin allows the user to select fixed frequency PWM mode or enables the Deep-SLLM control and the mode is automatically switched between the Deep-SLLM control and fixed frequency PWM mode. Include OCP (Over Current Protection) and SCP (Short Circuit Protection). Evaluation Board Operating Limits and Absolute Maximum Ratings (Ta=25) Limit Parameter Symbol Unit Conditions MIN TYP MAX Supply Voltage V 2.7 - 5.5 V CC V - 1.8 - V OUT Output Voltage / Current I - - 4 A OUT Evaluation Board Figure 1. BD9A400MUV-EVK-001 Evaluation Board www .rohm.co.jp 18 March 2015 Rev.001 2015 ROHM Co., Ltd. All rights reserved. 1/9 BD9A400MUV-EVK-001 Operation Procedures 1. Necessary equipments (1) DC power-supply of 2.7V to 5.5V/4A (2) Maximum 4A load (3) DC voltmeter 2. Connecting the equipments (1) DC power-supply presets to 5.0V and then the power output turns off. (2) The max. load should be set at 4A and over it will be disabled. (3) Check Jumper pin of SW1 is short, between intermediate-terminal and OFF-side terminal. (4) Connect positive-terminal of power-supply to VIN+terminal and negative-terminal to GND-terminal with a pair of wires. (5) Connect loads positive-terminal to VOUT+terminal and negative-terminal to GND-terminal with a pair of wires. (6) Connect positive-terminal of DC voltmeter 1 to TP1 and negative-terminal to TP2 for input-voltage measurement. (7) Connect positive-terminal of DC voltmeter 2 to TP3 and negative-terminal to TP4 for output-voltage measurement. (8) DC power-supply output is turned ON. (9) IC is enable (EN) by shorting Jumper-pin of SW1 between intermediate-terminal and ON-side terminal. (10) Check DC voltmeter 2 displays 1.8V. (11) The load is enabled. (12) Check at DC voltmeter 1 whether the voltage-drop (loss) is not caused by the wires resistance. + DC Voltmeter 2 V + DC Voltmeter 1 V - - + + DC Power Load - - Figure 2. Connection Diagram Enable-Pin To minimize current consumption during standby-mode and normal operation, Enable-mode can be switched by controlling EN pin(15pin) of the IC. Standby-mode is enabled by shorting Jumper-pin of SW1 between intermediate-terminal and OFF-side terminal and normal-mode operation by shorting between intermediate-terminal and ON-side terminal. It also can be swithed between standby-mode and normal-mode operation by removing Jumper-pin and controlling the voltage between EN and GND-terminal. Standby-mode is enabled when the voltage of EN is under 0.5V, and normal-mode operation when it is over 2.0V. www.rohm.co.jp 18 March 2015 Rev.001 2015 ROHM Co., Ltd. All rights reserved. 2/9