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Philips Semiconductors Linear Products
Quad timer
558 EQUIVALENT CIRCUIT
VCC
Product specification
NE558
TIMING
VCONTROL
+ 3V
RESET
TRIGGER
OUT
GND
TRIGGER
VCC
R1 RL
R1 RL
R1 RL
R1 RL
T
C1
T
C1
T
C1
T
C2
TRIGGER
OUTPUT 1
OUTPUT 2
TR 0
TR 0
TR 0
TR 0
OUTPUT 1
OUTPUT 2
NOT USED
OUTPUT 3
OUTPUT 4
OUTPUT 3
OUTPUT 4
TDELA
Y
TDELAY 3(R1C)
TOUT R2C2)
Figure 1. Long-Time Delay
TOUTPUT
August 31, 1994
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