Installation and Operation
© 2011 Microchip Technology Inc. DS51999A-page 15
2.2 GETTING STARTED
The MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design is fully
assembled and tested to evaluate and demonstrate the MCP1640 family of products.
2.2.1 Powering the MCP1640 12V/50 mA Two Cells Input Boost
Converter Reference Design
The extended input range of the MCP1640 Input Boost Converter is 2.0 to 5.0V input.
Good efficiency is obtained by supplying from two cells (primary and secondary batter-
ies).
Input power connectors are placed on the left side of the board:
•V
IN
for positive power
• GND for negative power
The maximum input voltage should not exceed 5.0V. The output voltage will be out of
regulation for input voltages lower than 2.0V.
The output connector is called V
OUT
and is referenced to GND. The minimum output
current is 50 mA when the board is powered by two alkaline batteries that are close to
the end of their run time, at approximately 1V each.
2.2.2 Board Testing
Because this board is boosting the input voltage, the input current is greater than the
output current. The variable power supply for testing requires output capability of at
least 1A and a voltage range of 2.0V to 5V.
To test the board, follow these steps:
1. Connect the power at V
IN
and GND terminals of the board.
2. Set the power supply to 3.0V.
3. Connect a voltmeter and a 240Ω/0.5W resistor between V
OUT
and GND
connectors, as shown in Figure 2-3.
4. Check to be sure the voltmeter indicates 12V.
5. Set the power supply to 2.0V and verify if the output of the converter stays
regulated (V
OUT
=12V).
FIGURE 2-3: MCP1640 12V/50 mA Two Cells Input Boost Converter Reference Design
Setup Circuit.
R
240R/0.5W
Set 3.0V
PWR Supply
V-meter
