NE555
SA555 - SE555
General purpose single bipolar timers
Features
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Low turn off time
Maximum operating frequency greater than
500kHz
Timing from microseconds to hours
Operates in both astable and monostable
modes
High output current can source or sink 200mA
Adjustable duty cycle
TTL compatible
Temperature stability of 0.005% per °C
D
SO8
(Plastic micropackage)
N
DIP8
(Plastic package)
Description
The NE555 monolithic timing circuit is a highly
stable controller capable of producing accurate
time delays or oscillation. In the time delay mode
of operation, the time is precisely controlled by
one external resistor and capacitor. For a stable
operation as an oscillator, the free running
frequency and the duty cycle are both accurately
controlled with two external resistors and one
capacitor.
The circuit may be triggered and reset on falling
waveforms, and the output structure can source
or sink up to 200mA.
Pin connections
(top view)
1
2
3
4
8
7
6
5
1 - GND
2 - Trigger
3 - Output
4 - Reset
5 - Control voltage
6 - Threshold
7 - Discharge
8 - V
CC
March 2007
Rev 4
1/20
20
STMICROELECTRONICS [ STMICROELECTRONICS ]
