Recommended equipment

AN2938

14/39

Doc ID 15429 Rev 1

7

Recommended equipment

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6 V to 28 V power supply, notebook battery or AC adapter

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Active loads

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Digital multimeters

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500 MHz four-trace oscilloscope

8

Quick start

1.

Connect the VIN+ and VIN- test points of the demonstration board to an external 12 V

power supply.

2.

Ensure that all jumpers EN1, EN2 and EN_LDO are connected to GND. In this

condition all outputs are disabled (shutdown mode).

3.

Set jumper EN_LDO at input resistor divider (EN_LDO pin high). The LDO output

4.

Set jumper EN1 at VCC (EN1 pin high). The OUT1 switching controller brings its output

into regulation. The PG1 pin goes high after soft-start.

5.

Set jumper EN2 at VCC (EN2 pin high). The OUT2 switching controller brings its output

into regulation. The PG2 pin goes high after soft-start.

6.

In order to load the switching outputs, loads must be connected between the “+” and

the “-” output test points, respectively.

a.

In this setup, the VCC external supply is directly supplied by output LDO = 5 V. It is possible to disconnect LDO

from VCC by disconnecting jumper LDO5V_BYP: in this case VCC external supply is needed before

performing the “quick start” procedure.