MIC2207YML-EV Microchip

MIC2207 Evaluation Board 3mm 3mm 2MHz Buck Converter General Description The Micrel MIC2207 is a high efficiency PWM buck provide power to the device, the inductance can be over (step-down) regulator that provides up to 3A of output 1uH. During a short circuit condition, the high peak current. The MIC2207 operates at 2MHz and has currents through the test leads may cause the input proprietary internal compensation that allows a closed voltage to spike and exceed the absolute maximum loop bandwidth of over 200 KHz rating of 6V, possibly damaging the device. The low on-resistance internal p-channel MOSFET of Getting Started the MIC2207 allows efficiencies over 94% and reduces 1. Connect an external supply to V . Apply IN external component count and eliminates the need for desired input voltage to the V and ground IN an expensive current sense resistor. terminals of the evaluation board, paying careful The MIC2207 operates from 2.7V to 5.5V input and the attention to polarity and supply voltage output can be adjusted down to 1V. The devices can (2.7V<V <5.5V). An ammeter may be placed IN operate with a maximum duty cycle of 100% for use in between the input supply and the V terminal to IN low-dropout conditions. the evaluation board. Ensure the supply voltage is monitored at the V terminal. The ammeter IN Requirements and/or power lead resistance can reduce the The MIC2207 evaluation board requires an input power voltage supplied to the input. source that is able to deliver greater than 2.7V at over 2. Connect the load to the V and ground OUT 3A. The output load can either be an active or passive terminals. The load can be either passive source. (resistive) or active (as in an electronic load). An ammeter can be placed between the load and Precautions the V terminal. Ensure the output voltage is OUT The evaluation board does not have reverse polarity monitored at the V terminal. The default OUT protection. Applying a negative voltage to the V IN output voltage is set to 1.8V. This can be terminal may damage the device. adjusted by changing the feedback resistors. In addition, the maximum operating voltage of the See Output Voltage. MIC2207 evaluation board is 5.5V. Exceeding 6V on the 3. Enable the MIC2207. Apply a 1.3V or greater input could damage the device. For short circuit voltage source to the enable pin. testing, an additional input capacitor over 22uF is required. This is preferably an electrolytic, but may be tantalum or ceramic. When using long test leads to Typical Application MIC2207 Evaluation Board Schematic Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC2207 Evaluation Board The evaluation board is initially adjusted to 1.8V, but Output Voltage can easily be modified by removing R2 and replacing The output voltage on the MIC2207 evaluation board it with the value that yields the desired output voltage. is adjustable. The output voltage is controlled by the (Removing R2 sets the output to 1V.) feedback resistors (R1 and R2) and can be calculated 10k as follows: R2 = V OUT 1 R1 V = 1V + 1 1V OUT R2 2 M9999-051706 May 2006 (408) 955-1690