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74HC273 Datasheet, PDF (2/8 Pages) NXP Semiconductors – Octal D-type flip-flop with reset; positive-edge trigger
Philips Semiconductors
Octal D-type flip-flop with reset;
positive-edge trigger
Product specification
74HC/HCT273
FEATURES
• Ideal buffer for MOS microprocessor or memory
• Common clock and master reset
• Eight positive edge-triggered D-type flip-flops
• See “377” for clock enable version
• See “373” for transparent latch version
• See “374” for 3-state version
• Output capability; standard
• ICC category: MSI
GENERAL DESCRIPTION
The 74HC/HCT273 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/HCT273 have eight edge-triggered, D-type
flip-flops with individual D inputs and Q outputs. The
common clock (CP) and master reset (MR) inputs load and
reset (clear) all flip-flops simultaneously.
The state of each D input, one set-up time before the
LOW-to-HIGH clock transition, is transferred to the
corresponding output (Qn) of the flip-flop.
All outputs will be forced LOW independently of clock or
data inputs by a LOW voltage level on the MR input.
The device is useful for applications where the true output
only is required and the clock and master reset are
common to all storage elements.
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
SYMBOL PARAMETER
CONDITIONS
tPHL/ tPLH
fmax
CI
CPD
propagation delay
CP to Qn
MR to Qn
maximum clock frequency
input capacitance
power dissipation capacitance per flip-flop
CL = 15 pF; VCC = 5 V
notes 1 and 2
Notes
1. CPD is used to determine the dynamic power dissipation (PD in µW):
PD = CPD × VCC2 × fi + ∑ (CL × VCC2 × fo) where:
fi = input frequency in MHz
fo = output frequency in MHz
∑ (CL × VCC2 × fo) = sum of outputs
CL = output load capacitance in pF
VCC = supply voltage in V
2. For HC the condition is VI = GND to VCC
For HCT the condition is VI = GND to VCC − 1.5 V
TYPICAL
UNIT
HC HCT
15 15 ns
15 20 ns
66 36 MHz
3.5 3.5 pF
20 23 pF
ORDERING INFORMATION
See “74HC/HCT/HCU/HCMOS Logic Package Information”.
September 1993
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