Datasheet

September 1993 2
Philips Semiconductors Product specification
Programmable delay timer with oscillator 74HC/HCT5555
FEATURES
• Positive and negative edge
triggered
• Retriggerable or non-retriggerable
• Programmable delay
minimum: 100 ns
maximum: depends on input
frequency and division ratio
• Divide-by range of 2 to 2
24
• Direct reset terminates output
pulse
• Very low power consumption in
triggered start mode
• 3 oscillator operating modes:
– RC oscillator
– Crystal oscillator
– External oscillator
• Device is unaffected by variations
in temperature and V
CC
when using
an external oscillator
• Automatic power-ON reset
• Schmitt trigger action on both
trigger inputs
• Direct drive for a power transistor
• Low power consumption in active
mode with respect to TTL type
timers
• High precision due to digital timing
• Output capability: 20 mA
• I
CC
category: MSI.
APPLICATIONS
• Motor control
• Attic fan timers
• Delay circuits
• Automotive applications
• Precision timing
• Domestic appliances.
GENERAL DESCRIPTION
The 74HC/HCT5555 are high-speed
Si-gate CMOS devices and are pin
compatible with low power Schottky
TTL (LSTTL). They are specified in
compliance with JEDEC standard
no. 7A.
The 74HC/HCT5555 are precision
programmable delay timers which
consist of:
• 24-stage binary counter
• integrated oscillator (using external
timing components)
• retriggerable/non-retriggerable
monostable
• automatic power-ON reset
• output control logic
• oscillator control logic
• overriding asynchronous master
reset (MR).
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25 °C; t
r
= t
f
= 6 ns.
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in µW):
P
D
= C
PD
x V
CC
2
x f
i
+ Σ(C
L
x V
CC
2
x f
o
) where:
f
i
= input frequency in MHz
f
o
= output frequency in MHz
Σ(C
L
x V
CC
2
x f
o
) = sum of outputs.
C
L
= output load capacitance in pF
V
CC
= supply voltage in V
2. For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
− 1.5 V.
ORDERING INFORMATION
SYMBOL PARAMETER CONDITIONS TYP. UNIT
t
PHL
/t
PLH
propagation delay C
L
= 15 pF;
V
CC
= 5 V
A,
B to Q/Q2424ns
MR to Q/
Q1920ns
RS to Q/
Q2628ns
C
I
input capacitance 3.5 3.5 pF
C
PD
power dissipation
capacitance per buffer
notes 1 and 2 23 36 pF
EXTENDED TYPE
NUMBER
PACKAGE
PINS PIN POSITION MATERIAL CODE
74HC/HCT5555N 16 DIL plastic SOT38Z
74HC/HCT5555D 16 SO16 plastic SOT109A