FEATURE DESCRIPTIONS (CON.
)
The output voltage tracking feature (Figure 35 to Figure
37) is achieved according to the different external
connections. If the tracking feature is not used, the
TRACK pin of the module can be left unconnected or tied
to Vin.
For proper voltage tracking, input voltage of the tracking
power module must be applied in advance, and the
remote on/off pin has to be in turn-on status. (Negative
logic: Tied to GND or unconnected. Positive logic: Tied to
Vin or unconnected)
Sequential Start-up
Sequential start-up (Figure 35) is implemented by placing
an On/Off control circuit between Vo
PS1
and the On/Off pin
of PS2.
PS1
Vin
Vo
PS1
Vin
Vo
PS2
On/Off
R1
On/Off
R2
Q1
C1
PS2
R3
PS1
PS2
PS1
PS2
Simultaneous
Simultaneous tracking (Figure 36) is implemented by
using the TRACK pin. The objective is to minimize the
voltage difference between the power supply outputs
during power up and down.
Figure 35:
Sequential start-up
PS1
PS2
PS1
PS2
The simultaneous tracking can be accomplished by
connecting Vo
PS1
to the TRACK pin of PS2. Please note
the voltage apply to TRACK pin needs to always higher
than the Vo
PS2
set point voltage.
PS1
Vin
Vo
PS1
Vin
PS2
Vo
PS2
Figure 36:
Simultaneous
On/Off
TRACK
On/Off
PS1
+△V
PS2
PS1
PS2
Figure 37:
Ratio-metric
DS_DNL10SMD_07182012
11
DELTA [ DELTA ELECTRONICS, INC. ]
