Datasheet

www.ti.com
V =1.5V
O
V =3.3V
I
R
8.87k
SET
W
ASIC
VCORE
VCCIO
I
O
PTV03020W
Track
V
I
V
O
GND
Vadj
Sense
+
C1
+
C3
+
C2
Output Remote Sense
PTV03020W
SLTS243A – FEBRUARY 2005 – REVISED OCTOBER 2007
ground signal applied to the Inhibit control input), the input voltage must always be greater than the applied
prebias source. This condition must exist throughout the power-up sequence of the power system.
Figure 16. Application Circuit Demonstrating Prebias Start-Up
Products with this feature incorporate an output voltage sense input, V
O
Sense. A remote sense improves the
load regulation performance of the module by allowing it to compensate for any remote IR voltage drop between
its output and the load. An IR drop is caused by the output current flowing through the small amount of pin and
trace resistance.
To use this feature, simply connect V
O
Sense to the V
O
node, close to the load circuit (see the data sheet
standard application). If the V
O
Sense input is left open-circuit, an internal low-value resistor (15 Ω or less)
connected between the pin and the output node, ensures that the output remains in regulation.
With the sense input connected, the difference between the voltage measured directly between the V
O
and GND
pins, and that measured from V
O
Sense to GND, is the amount of IR drop being compensated by the regulator.
This should be limited to a maximum of 0.3 V.
Note: The remote sense feature is not designed to compensate for the forward drop of nonlinear or frequency
dependent components that may be placed in series with the output. Examples include OR-ing diodes, filter
inductors, ferrite beads, and fuses. When these components are enclosed by the remote sense connection, they
are effectively placed inside the regulation control loop, which can adversely affect the stability of the module.
16 Submit Documentation Feedback Copyright © 2005 – 2007, Texas Instruments Incorporated
Product Folder Link(s) :PTV03020W