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DEVICE INFORMATION

PIN 1

)

V

- 0.8

O

0.8

- 7.135 kW

(

R

= 30.1

SET

x

PTV08T250W

SLTS260B – OCTOBER 2005 – REVISED NOVEMBER 2005

PTV08T250W

(Top View)

TERMINAL FUNCTIONS

TERMINAL

DESCRIPTION

NAME

NO.

4, 5, 11, 12, 18,

GND

19

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.

further information, see the Application Information section.

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.

This input pin adjusts the transient response of the regulator. For a given value of output capacitance, a

reduction in peak output voltage deviation and increased system stability is achieved by placing a resistor

between this pin and +Sense. A 1%, 0.05-W resistor must be connected between this pin and +Sense to

TurboTrans

9

activate the TurboTrans feature. Suggested placement of this resistor is within 1 cm from pin 9. The

resistor value required can be selected from the TurboTrans resistor table. If unused, this input pin

should be left open-circuit. For further information, see the related Application Information section.

5