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Figure 7
AC OK Power Fail
Auxiliary VCC +5V / 0.3A (J10-9)
The VCC on J10-9 is an auxiliary 5V regulated power source (see Figure 8 and Connector Pin
Identification on Page 16). It is +5V
DC
±5% with respect to Signal Ground and can supply 300mA
maximum. It is short-circuit-proof, but if shorted all outputs will shut down through the Enable / Disable
circuitry. The Auxiliary VCC typically powers user circuitry or is used with the Power Good circuitry to
provide a pull-up reference for the outputs of the DC Power Good circuit on a ConverterPAC™. If used
for this purpose, the Signal Ground on J10-10 must also be connected to the J3-1 Signal Ground pin of
the ConverterPAC.
Power Good (J2-3 / P2-3)
The optional Power Good signal on J2-3 / P2-3 is referenced to Signal Ground on J2-1 / P2-1 and
indicates the status of the output voltage. This signal is asserted a TTL “1” when the output voltage
is above 95% of nominal. It is a TTL “0” when the output voltage is below 85% of nominal. If the
Trim option is also used, the Power Good trip points DO NOT track with the trimmed voltage. It is
possible to trim the output below the fixed set points of the Power Good circuit and cause a negative
Power Good signal.
10kΩ
Signal Ground
AC Power OK
11
+5V
10
J10
2.49K
PN2222
Figure 8
Auxiliary VCC
78M05
Auxiliary VCC
9
0.1µF
Signal Ground
J10
10
+5V/300mA
Figure 9
Power Good and VCC
Signal Ground
2
VCC IN
4
J2/P2
10kΩ
2.49kΩ
2N2222
2.49kΩ
1
Power Good
3
Power Good Inverted
