Microchip Technology MCP1012, Руководство пользователя

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MCP1012 1W Demonstration Board User’s Guide
DS50002932A-page 16

2020 Microchip Technology Inc.
FIGURE 3-1: MCP1012 V_GATE and V
DD
Hysteretic Voltage Supply at No
Load.
Note that the MCP1012 is hysteretic supplied, between the OVLO
ON
and OVLO
OFF
thresholds.
7. Disconnect the DC HV power supply.
3.2 SETUP 1B
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 a load is applied at the output
(the resistor R21 - 68

is connected through SW1.2)
STEPS
1. Connect/disconnect the jumpers and the switch SW1 according to Table 3-2 .
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: SW1.2 is the second 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 TP1 (V
DD
Input) and TP6 (GATE
output). Connect the ground probes on the primary side, at the TP14 or TP15
Test Points.
TABLE 3-2: THE STATE OF THE JUMPERS AND SWITCH - SETUP 1B
J1 J2 J3 J4 J5 J6 J7 JP1 SW1.1 SW1.2 SW1.3 SW1.4
ON OFF ON
1
OFF OFF OFF OFF ON
1
OFF ON
2
OFF OFF