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PTH04T220/221W

(TOP VIEW)

PTH04T220W, PTH04T221W

SLTS275A – DECEMBER 2006 – REVISED FEBRUARY 2007

TERMINAL FUNCTIONS

TERMINAL

DESCRIPTION

NAME

NO.

1

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

4

The regulated positive power output with respect to GND.

GND

2, 3

the control inputs.

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 a valid input source is applied.

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UVLO

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

GND (pin 3) allows the ON threshold of the UVLO to be adjusted higher than the default value. For more

information, see the Application Information section.

A 0.05 W 1% resistor must be directly connected between this pin and pin 6 (–Sense) to set the output voltage

to a value higher than 0.69 V. The temperature stability of the resistor should be 100 ppm/

°C (or better). The

setpoint range for the output voltage is from 0.69 V to 3.6 V. If left open circuit, the output voltage will default to

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its lowest value. For further information, on output voltage adjustment see the related application note.

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

The sense input allows the regulation circuit to compensate for voltage drop between the module and the load.

+ Sense

5

The sense input allows the regulation circuit to compensate for voltage drop between the module and the load.

– Sense

6

For optimal voltage accuracy –Sense must be connected to GND (pin 3) very close to the module (within

10 cm).

This is an analog control input that enables the output voltage to follow an external voltage. This pin becomes

active typically 20 ms after the input voltage has been applied, and allows direct control of the output voltage

from 0 V up to the nominal set-point voltage. Within this range the module's output voltage follows the voltage at

Track

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the Track pin on a volt-for-volt basis. When the control voltage is raised above this range, the module regulates

at its set-point voltage. The feature allows the output voltage to rise simultaneously with other modules powered

NOTE: Due to the undervoltage lockout feature, the output of the module cannot follow its own input voltage

during power up. For more information, see the related application note.

This input pin adjusts the transient response of the regulator. To activate the TurboTrans™ feature, a 1%,

50 mW resistor must be connected between this pin and pin 5 (+Sense) very close to the module. For a given

value of output capacitance, a reduction in peak output voltage deviation is achieved by utililizing this feature. If

TurboTrans™

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unused, this pin must be left open-circuit. The resistance requirement can be selected from the TurboTrans™

resistor table in the Application Information section. External capacitance must never be connected to this pin

unless the TurboTrans resistor value is a short, 0

Ω.

This input pin sychronizes the switching frequency of the module to an external clock frequency. The SmartSync

feature can be used to sychronize the switching fequency of multiple PTH04T220/221W modules, aiding EMI

SmartSync

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noise suppression efforts. If unused, this pin should be connected to GND (pin 3). For more information, please

review the Application Information section.

(1)

Denotes negative logic: Open = Normal operation, Ground = Function active

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