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DEVICE INFORMATION

PIN1

)

V

-0.8

O

0.8

-7.135kW

(

R

=30.1

SET

x

PTV08040W

SLTS257A – SEPTEMBER 2005 – REVISED JANUARY 2007

PTV08040W

(Top View)

TERMINAL FUNCTIONS

TERMINAL

DESCRIPTION

NAME

NO.

4, 5, 11, 12, 18,

GND

19

reference for the control inputs.

6, 7, 13, 14, 20,

The positive input voltage power node to the module, which is referenced to common GND.

21

3, 10, 17

The regulated positive power output with respect to GND.

The Inhibit pin is an open-collector/drain negative logic input that is referenced to GND. Applying a

low-level ground signal to this input disables the module’s output and turns off the output voltage. When

the Inhibit control is active, the input current drawn by the regulator is significantly reduced. If the Inhibit

pin is left open-circuit, the module produces an output whenever the input voltage is above the UVLO

Inhibit /

16

threshold.

UVLO

This pin is also used for input undervoltage lockout (UVLO) programming. Connecting a resistor from

this pin to signal ground allows the ON threshold of the UVLO to be adjusted higher than the default

value. The hysterisis can also be independently reduced by connecting a second resistor from this pin to

A 1%, 0.05-W resistor must be connected between this pin and GND to set the output voltage higher

than the minimum value. The set-point range for the output voltage is from 0.8 V to 3.6 V. The resistor

8

required for a given output voltage may be calculated from the following formula. If left open circuit, the

module output defaults to its lowest output voltage value. For further information on the adjustment

and/or trimming of the output voltage, see the related Application Information section.

The specification table gives the preferred resistor values for a number of standard output voltages.

The sense inputs allow the regulation circuit to compensate for voltage drop between the module and the

+Sense

1

internal resistor ensures that the output remains in regulation.

For optimal voltage accuracy, –Sense should be connected to the ground return at the load. If it is left

–Sense

2

open, a low-value internal resistor ensures that the output remains in regulation.

This is an analog control input that allows the output voltage to follow another voltage during power up

and power down sequences. The pin is active from 0 V, up to the nominal set-point voltage. Within this

range, the module output follows the voltage at the Track pin on a volt-for-volt basis. When the control

Track

15

voltage is raised above this range, the module regulates at its nominal output voltage. If unused, this

Information section.

N/C

9

No Connection

4

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