TPS77115DGK datasheet(15/25 Pages) TI

15 / 25 page

TPS77101/115/118/127/128/133/150 WITH RESET OUTPUT

TPS77201/215/218/227/228/233/250 WITH POWER GOOD OUTPUT

150-mA LDO REGULATORS WITH 8-PIN MSOP PACKAGING

SLVS225D – FEBRUARY 2000 – REVISED OCTOBER 2000

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

APPLICATION INFORMATION

pin functions

enable (EN)

The EN terminal is an input which enables or shuts down the device. If EN is a logic high, the device will be in

shutdown mode. When EN goes to logic low, then the device will be enabled.

power good (PG) (TPS772xx)

The PG terminal is an open drain, active high output that indicates the status of Vout (output of the LDO). When

Vout reaches 82% of the regulated voltage, PG will go to a high-impedance state. It will go to a low-impedance

state when Vout falls below 82% (i.e. over load condition) of the regulated voltage. The open drain output of the

PG terminal requires a pullup resistor.

sense (SENSE)

The SENSE terminal of the fixed-output options must be connected to the regulator output, and the connection

should be as short as possible. Internally, SENSE connects to a high-impedance wide-bandwidth amplifier

through a resistor-divider network and noise pickup feeds through to the regulator output. It is essential to route

the SENSE connection in such a way to minimize/avoid noise pickup. Adding RC networks between the SENSE

terminal and Vout to filter noise is not recommended because it may cause the regulator to oscillate.

feedback (FB)

FB is an input terminal used for the adjustable-output options and must be connected to an external feedback

resistor divider. The FB connection should be as short as possible. It is essential to route it in such a way to

minimize/avoid noise pickup. Adding RC networks between FB terminal and Vout to filter noise is not

recommended because it may cause the regulator to oscillate.

reset (RESET) (TPS771xx)

The RESET terminal is an open drain, active low output that indicates the status of Vout. When Vout reaches 95%

of the regulated voltage, RESET will go to a high-impedance state after a 220-ms delay. RESET will go to a

low-impedance state when Vout is below 95% of the regulated voltage. The open-drain output of the RESET

terminal requires a pullup resistor.

TPS77115DGK Datasheet(PDF) 15 Page - Texas Instruments