TS803R

1-1

2003/12 rev. E

TS803R

Microprocessor Reset Circuit

Open Drain

Threshold Voltage Option

2.7V, 2.93V, 4.2V

General Description

The TS803R are microprocessor (µP) supervisory circuit used to monitor the power supplies in µP and digital systems.

They provide excellent circuit reliability and low cost by eliminating external components and adjustments when used with

+5V, +3.3V, +3.0V powered circuits. These circuits perform a single function: they assert a reset signal whenever the

VCC supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after VCC has risen above

the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available. The TS803R

are open –drain outputs. The TS803R have an active low RESET output, while the TS803R has an active high RESET

output. The reset comparator is designed to ignore fast transients on VCC, and the output guaranteed to be in the correct

logic state for VCC down to 1V. Low supply correct makes the TS803R ideal for use in portable equipment.

The TS803R is available in a 3-pin SOT-23 package.

Features

Precision monitoring of +3V, +3.3V and +5V

power supply voltage

Fully specified over temperature

Available in three output configurations

Open – Drain RESET low output

3uA supply current

Guaranteed reset valid to Vcc = +1V

Power supply transient immunity

No external components

Ordering Information

Note: x is the threshold voltage type, option as

B: 4.20V

E: 2.93V

F: 2.70V

Part No.

Enable

Function

Threshold

Voltage

Package

TS803RCX B

Active-Low

4.2V

TS803RCX E

Active-Low

2.93V

TS803RCX F

Active-Low

2.7V

SOT-23

Applications

Computers

Controllers

Intelligent instruments

Critical uP and uC power monitoring

Portable / Battery powered equipment

Automotive

Pin Descriptions

Pin No.

Name

Description

1

RESET

Reset output pin

(Active- Low)

2

Gnd

Ground

3

Vcc

Operating voltage input

Absolute Maximum Rating

Supply Voltage

7

V

RESET & (RESET) push-pull

V

Input Current, Vcc

20

mA

Output Current, RESET

20

mA

Rate of Rise, Vcc

100

V/uS

Pin assignment

TS803R

1.

RESET

2.

Gnd

3.

Vcc