Datasheet

DS_DNM10SMD10_07182012
10
FEATURE DESCRIPTIONS (CON.)
The output voltage tracking feature (Figure 27 to Figure
29) 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)
Figure 27: Sequential start-up
Figure 28: Simultaneous
Figure 29: Ratio-metric
PS1
PS1
PS2
PS2
PS1
PS1
PS2
PS2
Sequential Start-up
Sequential start-up (Figure 27) is implemented by placing
an On/Off control circuit between Vo
PS1
and the On/Off pin
of PS2.
R1
R2
Vo
PS1
PS1
Vin
On/Off
On/Off
PS2
Vo
PS2
Vin
C1
Q1
R3
Simultaneous
Simultaneous tracking (Figure 28) 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.
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.
TRACK
Vo
PS1
PS2
Vo
PS2
PS1
Vin
Vin
On/Off
On/Off
PS1
PS2
PS1
PS2
+△V