IC
INTEGRATED CIRCUIT
SINGLE PRECISION TIMER
JM3851010901BPA
NC ? No internal connection
NA555...D OR P PACKAGE
NE555...D, P, PS, OR PW PACKAGE
SA555...D OR P PACKAGE
SE555...D, JG, OR P PACKAGE
(TOP VIEW)
SE555...FK PACKAGE
(TOP VIEW)
NA555, NE555, SA555, SE555
PRECISION TIMERS
SLFS022F?SEPTEMBER 1973?REVISED JUNE 2006
? Timing From Microseconds to Hours ? Adjustable Duty Cycle
? Astable or Monostable Operation ? TTL-Compatible Output Can Sink or Source
up to 200 mA
These devices are precision timing circuits capable of producing accurate time delays or oscillation. In the
time-delay or Monostable mode of operation, the timed interval is controlled by a single external resistor and
capacitor network. In the astable mode of operation, the frequency and duty cycle can be controlled
independently with two external resistors and a single external capacitor.
The threshold and trigger levels normally are two-thirds and one-third, respectively, of VCC. These levels can be
altered by use of the control-voltage terminal. When the trigger input falls below the trigger level, the flip-flop is
set, and the output goes high. If the trigger input is above the trigger level and the threshold input is above the
threshold level, the flip-flop is reset and the output is low. The reset (RESET) input can override all other inputs
and can be used to initiate a new timing cycle. When RESET goes low, the flip-flop is reset, and the output goes
low. When the output is low, a low-impedance path is provided between discharge ( DISCH ) and ground.
The output circuit is capable of sinking or sourcing current up to 200 mA. Operation is specified for supplies of
5 V to 15 V. With a 5-V supply, output levels are compatible with TTL inputs.
NOTE:
ALL ELECTRONICS ARE UNTESTED
SOLD AS IS