PHILIPS 74HC242

INTEGRATED CIRCUITS
DATA SHEET
For a complete data sheet, please also download:
• The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
74HC/HCT242
Quad bus transceiver; 3-state;
inverting
Product specification
File under Integrated Circuits, IC06
December 1990
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
FEATURES
• Inverting 3-state outputs
The 74HC/HCT242 are quad bus transceivers featuring
inverting 3-state bus compatible outputs in both send and
receive directions.
They are designed for 4-line asynchronous 2-way data
communications between data buses.
• 2-way asynchronous data bus communication
• Output capability: bus driver
• ICC category: MSI
The output enable inputs (OEA and OEB) can be used to
isolate the buses.
GENERAL DESCRIPTION
The 74HC/HCT242 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
The “242” is similar to the “243” but has inverting outputs.
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
TYPICAL
SYMBOL
PARAMETER
UNIT
CONDITIONS
HC
tPHL/ tPLH
propagation delay
An to Bn;
Bn to An
CI
CL = 15 pF; VCC = 5 V
HCT
7
10
ns
input capacitance
3.5
3.5
pF
CI/O
input/output capacitance
10
10
pF
CPD
power dissipation capacitance per transceiver
29
32
pF
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
ORDERING INFORMATION
See “74HC/HCT/HCU/HCMOS Logic Package Information”.
December 1990
2
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
1
OEA
output enable input (active LOW)
2, 12
n.c.
not connected
3, 4, 5, 6
A0 to A3
data inputs/outputs
7
GND
ground (0 V)
11, 10, 9, 8
B0 to B3
data inputs/outputs
13
OEB
output enable input
14
VCC
positive supply voltage
Fig.1 Pin configuration.
December 1990
Fig.2 Logic symbol.
3
Fig.3 IEC logic symbol.
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
FUNCTION TABLE
INPUTS
INPUTS/OUTPUTS
OEA
OEB
An
Bn
L
H
L
H
L
L
H
H
inputs
Z
Z
A=B
B=A
Z
Z
inputs
Note
1. H = HIGH voltage level
L = LOW voltage level
Z = high impedance OFF-state
Fig.4 Functional diagram.
December 1990
4
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: bus driver
ICC category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
TEST CONDITIONS
74HC
SYMBOL PARAMETER
+25
−40 to +85
min. typ. max. min.
max.
−40 to +125
UNIT V
WAVEFORMS
CC
(V)
min. max.
tPHL/ tPLH
propagation delay
An to Bn;
Bn to An
25
9
7
90
18
15
115
23
20
135
27
23
ns
2.0
4.5
6.0
Fig.5
tPZH/ tPZL
3-state output enable time
OEA to An or Bn;
OEB to An or Bn
41
15
12
150
30
26
190
38
33
225
45
38
ns
2.0
4.5
6.0
Figs 6 and 7
tPHZ/ tPLZ
3-state output disable time
OEA to An or Bn;
OEB to An or Bn
52
19
15
150
30
26
190
38
33
225
45
38
ns
2.0
4.5
6.0
Figs 6 and 7
tTHL/ tTLH
output transition time
14
5
4
60
12
10
75
15
13
90
18
15
ns
2.0
4.5
6.0
Fig.5
December 1990
5
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: bus driver
ICC category: MSI
Note to HCT types
The value of additional quiescent supply current (∆ICC) for a unit load of 1 is given in the family specifications.
To determine ∆ICC per input, multiply this value by the unit load coefficient shown in the table below.
INPUT
UNIT LOAD COEFFICIENT
An
Bn
OEA
OEB
1.10
1.10
1.00
1.00
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
TEST CONDITIONS
74HCT
SYMBOL PARAMETER
+25
min.
−40 to +85
−40 to +125
typ.
max. min. max. min. max.
UNIT V
WAVEFORMS
CC
(V)
tPHL/ tPLH
propagation delay
An to Bn;
Bn to An
12
20
25
30
ns
4.5
Fig.5
tPZH/ tPZL
3-state output enable time
OEA to An or Bn;
OEB to An or Bn
16
34
43
51
ns
4.5
Figs 6 and 7
tPHZ/ tPLZ
3-state output disable time
OEA to An or Bn;
OEB to An or Bn
22
35
44
53
ns
4.5
Figs 6 and 7
tTHL/ tTLH
output transition time
5
12
15
18
ns
4.5
Fig.5
December 1990
6
Philips Semiconductors
Product specification
Quad bus transceiver; 3-state; inverting
74HC/HCT242
AC WAVEFORMS
(1) HC : VM = 50%; VI = GND to VCC.
HCT : VM = 1.3 V; VI = GND to 3 V.
Fig.5 Waveforms showing the input (An, Bn) to output (Bn, An) propagation delays and the output transition times.
(1) HC : VM = 50%; VI = GND to VCC.
HCT : VM = 1.3 V; VI = GND to 3 V.
Fig.6 Waveforms showing the 3-state enable and disable times for input OEB.
(1) HC : VM = 50%; VI = GND to VCC.
HCT : VM = 1.3 V; VI = GND to 3 V.
Fig.7 Waveforms showing the 3-state enable and disable times for input OEA.
PACKAGE OUTLINES
See “74HC/HCT/HCU/HCMOS Logic Package Outlines”.
December 1990
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