MCP1012
1W DEMONSTRATION BOARD
USER’S GUIDE
2020 Microchip Technology Inc.
DS50002932A-page 15
Chapter 3. Setup One
3.1
SETUP 1A
INTRODUCTION
This setup will show the functioning of the MCP1012 in Start-Up mode when it is
supplied by the secondary side of the transformer and no load is applied at the output
(neither of the R20, R21, R22, or R23 resistors is connected).
STEPS
1. Connect/disconnect the jumpers and the switch SW1 according to
Note 1:
JP1 and J3 connections eliminate the galvanic isolation between the Primary Side
and the Secondary Side of the transformer. Specific safety procedures must be taken
into account. The MCP1012 is supplied from the secondary side of the transformer.
On the board JP1 is connected to PIN1 and PIN2.
2. Connect the voltmeter at the TB3 connector with the positive test probe at the
upper terminal.
3. If available, connect two oscilloscope probes at TP1 (V
DD
Input) and TP6 (GATE
output). Connect the ground probes on the primary side, at the TP14 or TP15
Test Points.
4. Connect the DC HV power supply in the range of 120–500 VDC at TB1:
- the positive terminal must be connected at the uppermost terminal of the TB1
PCB connector
- the negative terminal must be connected to the bottommost terminal of the TB1
PCB connector (the middle terminal of the TB1 PCB connector is not connected)
5. Read the voltmeter and check if the output voltage of the board is in the range of
4.5V to 5.5V.
6. Check on the oscilloscope screen the V
DD
voltage and the GATE signal as they
are presented in
.
TABLE 3-1:
STATE OF THE JUMPERS AND SWITCH - SETUP 1A
J1
J2
J3
J4
J5
J6
J7
JP1
SW1.1
SW1.2
SW1.3
SW1.4
ON
OFF
ON*
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
