Microchip Technology MCP1012, User Manual

Page: 19 / 44

MCP1012
1W DEMONSTRATION BOARD
USER’S GUIDE

2020 Microchip Technology Inc. DS50002932A-page 19
Chapter 4. Setup Two
4.1 SETUP 2
INTRODUCTION
This setup will show the functioning of the MCP1012 in Start-Up mode when it is
supplied by an external power supply (15V) at V
DD
pin and a load is applied at the
output (the resistor R20 - 51

is connected through SW1.1).
A voltage greater than 11.5V on V
DD
pin disables the internal HV regulator.
STEPS
1. Connect/disconnect the jumpers and the switch SW1 according to Table 4-1 .
Note 1: SW1.1 is the first switch on the right side of the board.
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 TP6 (GATE output) and TP8 (C/S
input). Connect the ground probes on the primary side, at the TP14 or TP15 Test
Points.
4. Connect the DC power supply 15V at the TB2 connector:
- the positive terminal must be connected at the upper terminal of the TB2 PCB
connector
- the negative terminal must be connected to the bottom terminal of the TB2 PCB
connector
5. Connect the DC HV power supply in the range of 120–500 VDC at the TB1
connector:
- 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)
6. Read the voltmeter and check if the output voltage of the board is in the range of
4.5V to 5.5V.
TABLE 4-1: THE STATE OF THE JUMPERS AND SWITCH - SETUP 2
J1 J2 J3 J4 J5 J6 J7 JP1 SW1.1 SW1.2 SW1.3 SW1.4
ON OFF OFF OFF OFF OFF OFF OFF ON
1
OFF OFF OFF