NE555/SA555/NA555

PRECISION TIMERS

NE555/SA555/NA555

Document number: DS35112 Rev. 4 - 2

2 of 14

www.diodes.com

February 2012

© Diodes Incorporated

Pin Descriptions

Pin Name

Pin Number

Description

GND

1

Ground

TRIG

2

OUT

3

Timer output

RESET

4

Reset active low

CONT

5

External adjustment of internal threshold and trigger voltages

THRES

6

DISCH

7

Low impedance discharge path

8

Chip supply voltage

Functional Block Diagram

RESET can override TRIG, which can override THRESH

Functional Table

Pin Name

Nominal Trigger

Voltage

Threshold

Voltage

Output

Discharge

Switch

GND

Irrelevant

Irrelevant

Low

On

TRIG

Irrelevant

High

Off

OUT

Low

On

RESET

As previously established