Figure 5
– Plot of PI2003 response time to reverse current detection
Picor Corporation • www.picorpower.com
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.
