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74HC244 Datasheet, PDF (2/7 Pages) NXP Semiconductors – Octal buffer/line driver; 3-state | |||
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Philips Semiconductors
Octal buffer/line driver; 3-state
Product speciï¬cation
74HC/HCT244
FEATURES
⢠Output capability: bus driver
⢠ICC category: MSI
GENERAL DESCRIPTION
The 74HC/HCT244 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/HCT244 are octal non-inverting buffer/line
drivers with 3-state outputs. The 3-state outputs are
controlled by the output enable inputs 1OE and 2OE.
A HIGH on nOE causes the outputs to assume a high
impedance OFF-state. The â244â is identical to the â240â
but has non-inverting outputs.
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
SYMBOL
PARAMETER
CONDITIONS
tPHL/ tPLH
CI
CPD
propagation delay
1An to 1Yn;
2An to 2Yn
input capacitance
power dissipation capacitance per buffer
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 Ã VCC2 Ã fi + â (CL Ã VCC2 Ã fo) where:
fi = input frequency in MHz
fo = output frequency in MHz
â (CL Ã VCC2 Ã 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 â 1.5 V
TYPICAL
HC
9
HCT
11
UNIT
ns
3.5
3.5
pF
35
35
pF
ORDERING INFORMATION
See â74HC/HCT/HCU/HCMOS Logic Package Informationâ.
December 1990
2
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