Figure 5 – Plot of PI2003 response time to reverse current detection

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PI2003-EVAL1 User Guide Rev 1.0 Page 6 of 8

3.3

Connect the electronic load to the output between

Vout and Gnd. Set the load current to 1 A.

3.4

Enable (turn ON) PS1 power supply output.

3.5

Turn on the electronic load.

3.6

Measure the voltage across Q1, connect a voltmeter

between Vout- and Vin1-, the voltmeter should read

less than 30 mV to assure that the MOSFET is fully

enhanced.

3.7

LED D1 should be off indicating that controller U1 has

no fault. LED D2 should be on indicating that U2 is in

a fault mode and the controller Gate pin output

is low.

3.8

Disable (turn OFF) PS1 power supply output.

3.9

Enable (turn ON) PS2 power supply output.

3.10 Measure the voltage across Q2, connect a voltmeter

between Vout- and Vin2-, the voltmeter should read

less than 30mV to assure that the MOSFET is fully

enhanced.

3.11 LED D2 should be off indicating that controller U2 has

no fault. LED D1 should be on indicating that U1 is in

a fault mode and the controller Gate pin output is

low.

3.12 Enable (turn ON) PS1 and PS2.

3.13 Increase output load to 5 A. The power source, PS1

and PS2, should share the load current equally if

there output voltages are equal. Both LEDs, D1 and

D2, should be off indicating that both controllers

Gate pin output is high.

4.0 Input short circuit test

4.1

Apply a short at one of the inputs (Vin1 or Vin2). The

short can be applied electronically using a MOSFET

connected between low side off the source (Vin1- or

Vin2-) and the return (Vin1+ or Vin2+) or simply by

connecting Vin- to the return. Measure the response

time between when the short is applied and the

MOSFET Gate turns off. An example for PI2003

response time to an input short circuit is shown in

Figure 5.