NE555 Datasheet, PDF (1/5 Pages) NXP Semiconductors – Timer

Precision Timer
NE555
Connection Diagram
SO-8 ^NE555M
FUNCTION TABLE
RESET TRIGGER
VOLTAGE
Low
High
High
High
Irrelevant
<1/3VDD
>1/3V DD
>1/3VDD
THRESHOLD
VOLTAGE
DISCHARGE
OUTPUT _SWITCH
Irrelevant
High
>2/3V_DD
<2/3V DD
Low
On
High
Off
Low
On
As previously established
DIP-8 NE555N
General Description
The NE555 is a highly stable device for generating accurate
time delays or oscillation. Additional terminals are provided
for triggering or resetting if desired. In the time delay mode of
operation, the time is precisely controlled by one external re-
sistor and capacitor. For astable operation as an oscillator,
the free running frequency and duty cycle are accurately
controlled with two external resistors and one capacitor. The
circuit may be triggered and reset on falling waveforms, and
the output circuit can source or sink up to 200mA or drive
TTL circuits.
Features
n Direct replacement for SE555/NE555
n Timing from microseconds through hours
n Operates in both astable and monostable modes
n Adjustable duty cycle
n Output can source or sink 200 mA
n Output and supply TTL compatible
n Normally on and normally off output
Applications
n Precision timing
n Pulse generation
n Sequential timing
n Time delay generation
n Pulse width modulation
n Pulse position modulation
n Linear ramp generator
Wing Shing Computer Components Co., (H.K.)Ltd.
Homepage: http://www.wingshing.com
Tel:[phone] Fax:[phone]
E-mail: [e-mail]
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