Diodes NA555 - Manual (Page 2)

NE555/SA555/NA555
PRECISION TIMERS
NE555/SA555/NA555
Document number: DS35112 Rev. 4 - 2
2 of 14
www.diodes.com
February 2012
© Diodes Incorporated
NEW PROD
UC
T
Pin Descriptions
Pin Name Pin Number Description
GND 1 Ground
TRIG 2 Trigger set 1/3V
CC
OUT 3 Timer output
RESET 4 Reset active low
CONT 5 External adjustment of internal threshold and trigger voltages
THRES 6 Threshold set to 2/3 V
CC
DISCH 7 Low impedance discharge path
V
CC
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 <1/3V
CC
Irrelevant High Off
OUT <1/3V
CC
<2/3V
CC
Low On
RESET <1/3V
CC
<2/3V
CC
As previously established