Libro Psicologia

NE555, SA555, SE555 PRECISION TIMERS
SLFS022C – SEPTEMBER 1973 – REVISED FEBRUARY 2002

D D D D D

Timing From Microseconds to Hours Astable or Monostable Operation Adjustable Duty CycleTTL-Compatible Output Can Sink or Source up to 200 mA Designed To Be Interchangeable With Signetics NE555, SA555, and SE555

NE555 . . . D, P, PS, OR PW PACKAGE SA555 . . . D OR P PACKAGE SE555 . . . D,JG, OR P PACKAGE (TOP VIEW)

GND TRIG OUT RESET

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8 7 6 5

VCC DISCH THRES CONT

description
These devices are precision timing circuits capable of producing accurate time delays oroscillation. 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 andduty cycle can be controlled independently with two external resistors and a single external capacitor.
SE555 . . . FK PACKAGE (TOP VIEW)

9 10 11 12 13 The threshold and trigger levels normallyare 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 NC– No internal connection 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. Thereset (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, alow-impedance path is provided between discharge (DISCH) and ground.

NC TRIG NC OUT NC

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3 2 1 20 19 18 17 16 15 14

NC GND NC VCC NC NC DISCH NC THRES NC
PACKAGE CERAMIC DIP (JG) — —SE555JG PLASTIC DIP (P) NE555P SA555P SE555P — —

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,...