Auxiliary Supply (Aux); Power On Signal (Ena); Inverter Output Good (Iog); Remote On/Off - TDK-Lambda CPFE500 Application Note

AUXILIARY SUPPLY (AUX)

AUX is a 19~14VDC output for external circuits that is not affected by the remote on/off control.
Ground for AUX output is the COM terminal which is internally connected to –ve sense terminal.
Maximum load current for AUX output is 20mA. Avoid overload or short circuit of the AUX terminal as this may
cause internal damage to the PSU.

POWER ON SIGNAL (ENA)

The ENA signal is an open collector output which indicates that the output voltage is above a fixed threshold
level. The signal becomes low when the main output voltage exceeds the fixed threshold. The signal has
hysteresis on rising and falling voltage thresholds.
Ground for ENA signal is the COM terminal
Rising output voltage threshold for ENA low :-
12V model 8V typ
24V model 19V typ
28V model 19V typ
48V model 33V typ
Falling output voltage threshold for ENA high :-
12V model 6V typ
24V model 15V typ
28V model 15V typ
48V model 28V typ
The specifications for the ENA signal are :-
Signal Type
Sink Current
Open circuit voltage

INVERTER OUTPUT GOOD (IOG)

The IOG signal is an open collector output which provides an indication that the switching inverter is operating.
The signal is low when the inverter is normally operating and high when the inverter stops or is operating
abnormally. Ground for IOG signal is the COM terminal.
Note that the IOG signal may also become high/unstable for the following conditions :-
Operation of output over current protection (OCP)
•
Light load conditions with parallel operation
•
Dynamic load conditions
•
The specifications for the IOG signal are :-
Signal Type
Sink Current
Open circuit voltage

REMOTE ON/OFF

The on/off control signal is isolated from input, output and other control signals by an optocoupler.
The voltage between on/off control terminals and other outputs/control lines should not exceed 60VDC.
Where higher isolation voltage is required, an external optocoupler should be employed – see Figure 12.
The PSU output is enabled when a voltage is applied to the on/off control terminals.
CPFE500F Application Note
Open collector referenced to COM terminal
10mA max
75V max
Open collector referenced to COM terminal
5mA max
35V max
Document Number : 61066 iss 2 Page 9 of 17