Datasheet
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FEATURES OF THE PTH/PTV FAMILY OF NONISOLATED WIDE OUTPUT ADJUST POWER
Soft-Start Power Up
C
I
PTV08040W
6,7
13,14
20,21
4 5 11
V
I
15
Track
GND
V
I
GND
V (5V/div)
I
I (2 A/div)
I
t-Time=4ms/div
V (1V/div)
O
PTV08040W
SLTS257B – SEPTEMBER 2005 – REVISED JANUARY 2008
MODULES
The Auto-Track feature allows the power-up of multiple PTH/PTV modules to be directly controlled from the
Track pin. However in a stand-alone configuration, or when the Auto-Track feature is not being used, the Track
pin should be directly connected to the input voltage, V
I
(see Figure 11 ).
Figure 11. Track Pin Connection
When the Track pin is connected to the input voltage the Auto-Track function is permanently disengaged. This
allows the module to power up entirely under the control of its internal soft-start circuitry. When power up is
under soft-start control, the output voltage rises to the set-point at a quicker and more linear rate.
From the moment a valid input voltage is applied, the soft-start control introduces a short time delay (typically
8 ms – 15 ms) before allowing the output voltage to rise.
Figure 12. Power-Up Waveform
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Product Folder Link(s): PTV08040W