MCP1726EV Microchip Technology, MCP1726EV Datasheet - Page 12

• Manufacturer Part Number: MCP1726EV
• Description: BOARD EVAL FOR MCP1726
• Manufacturer: Microchip Technology

Specifications of MCP1726EV

• Channels Per Ic: 1 - Single
• Voltage - Output: 0.8 ~ 5V
• Current - Output: 1A
• Voltage - Input: 2.3 ~ 6V
• Regulator Type: Positive Adjustable
• Operating Temperature: -40°C ~ 125°C
• Board Type: Fully Populated
• Utilized Ic / Part: MCP1726
• Processor To Be Evaluated: MCP1726
• Silicon Manufacturer: Microchip
• Silicon Core Number: MCP1726
• Kit Application Type: Power Management - Voltage Regulator
• Application Sub Type: LDO
• Kit Contents: Board Cables CD Docs
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

2.4
DS51550B-page 8
TESTING CIRCUIT 1 OF THE MCP1726 EVALUATION BOARD
2.4.1
Powering the MCP1726 Evaluation Board
1. Apply the input voltage to test points TP7 (VIN1) and TP8 (GND). Connect the
2. When input voltage is applied and is above the input UVLO threshold, the LDO
3. When input voltage is applied, the red portion of the D2 LED will illuminate. As
Applying the load to the MCP1726 Evaluation Board
1. To apply a load to VOUT1 of the MCP1726 Evaluation Board, the positive-side
2. The maximum output current of the MCP1726 is 1.0A. If the output load exceeds
2.4.2
The MCP1726 Evaluation Board comes with the output voltage preset to 2.5V. To
adjust the output voltage (VOUT1) of circuit 1, the potentiometer, R10, is used. R10 is
a top-side adjust potentiometer. If the desired output voltage is higher than 2.5V, raise
the input voltage to a level that is higher than your desired output voltage. Use a small
flathead screwdriver to adjust the R10 potentiometer and monitor the VOUT1 (TP12)
voltage. If your desired output voltage is less than 2.5V, the input voltage of the LDO
must be set to a minimum of 2.3V, as this is the minimum input voltage of the LDO. The
output voltage of the LDO can then be adjusted using the R10 potentiometer.
The potentiometer will allow you to adjust the output voltage over the full range of 0.8V
to 5.0V. If you would like to use fixed resistor values to set the output voltage of the
LDO, the potentiometer can be removed and the pads for the potentiometer can be
used to solder your fixed value resistors into the circuit.
positive side of the input source (+) to test point TP7 (VIN1). Connect the
negative, or return, side (–) of the input source to the test point TP8 (GND).
These two test points are located on the upper left side of the board. The power
supply input voltage must be in the specified operating range for the board to
operate correctly. The UVLO feature of the MCP1726 prevents the device from
operating when the input voltage is too low (see data sheet for UVLO thresholds).
output will turn on automatically. The SHDN1 input has been pulled up to VIN1
which turns the device on. The LDO output can be turned off by pulling the
SHDN1 input (TP9) low (short SHDN1 to GND).
long as input voltage is present, the red portion of this LED will be on.
of the load (+) should be connected to test point TP12 (VOUT1). The negative
side of the load (–) should be connected to test point TP10 (GND).
this level, the MCP1726 will go into current limit at 1.7A. If, during the overload
condition, the device junction temperature exceeds the overtemperature limit of
150°C, the output of the LDO will turn off and wait for the junction temperature to
cool down before turning the LDO output back on. Circuit 1 of the MCP1726 Eval-
uation Board evaluates the 3X3 DFN package. When operating at room ambient,
this circuit will go into overtemperature shutdown when the power dissipation in
the device reaches about 2.1W.
Power Input and Output Connections
Adjusting the Output Voltage of the LDO
© 2006 Microchip Technology Inc.