FEATURES

· Over-Voltage Protection and

Lockout: 12V, 5V, and 3.3V Supplies

· Over-Current Protection and

Lockout: 12V, 5V, and 3.3V Supplies

· Under-Voltage Protection and

Lockout: 12V Supplies

· Under-Voltage Detect: 5V and 3.3V Supplies

· Fault-Protection Output with Open-Drain

Output Stage

· Open-Drain, Power-Good Output Signal:

Monitors Power-Good Signal Input 3.3V and

5V Supplies

· 300ms Power-Good Delay

· 75ms Delay: 5V, 3.3V Power-Supply

Short-Circuit Turn-On Protection

· 2.3ms PSON Control To FPO Turn-Off Delay

· 38ms PSON Control Debounce

· Wide Supply Voltage Range: 4.5V to 15V

DESCRIPTION

The TPS3514 is a PC switching power-supply

system monitor with minimum external components.

It provides under-voltage lockout (UVLO),

over-voltage (OV), under-voltage (UV), over-current

(OC) protection circuits, power-good indicator, and

on/off control.

UVLO thresholds are 4.45V (on) and 3.65V (off).

Over-current protection (OCP) and over-voltage

protection (OVP) monitor 3.3V, 5V, and 12V

supplies. When an OC or OV condition is detected,

the power-good output (PGO) is asserted low and

the fault protection output (FPO) is latched high.

PSON from low-to-high resets the latch. The OCP

function will be enabled 75ms after PSON goes LOW

with PGI HIGH and a debounce of typically 38ms. A

built-in 2.3ms delay with 38ms debounce from PSON

to FPO output is enabled at turn-off.

An external resistor is connected between the RI pin

and the GND pin. This will program a precise I(REF)

for OCP function. The programmable I(REF) range is

from 12.5mA to 62.5mA. Three OCP comparators and

the I(REF) section are supplied by VS12. The current

draw from the VS12 pin is less than 1mA.

The power-good feature monitors PGI, the 3.3V and

5V supplies, and issues a power-good signal when

the output is ready.

The TPS3514 is characterized for operation from

–40°C to +85°C. The TPS3514 is available in DIP-14

and SO-14 packages.