MC74HCT157A Datasheet, PDF (3/5 Pages) Motorola, Inc – Quad 2-Input Data Selector/Multiplexer with LSTTL-Compatible Inputs

MC74HCT157A
AC ELECTRICAL CHARACTERISTICS (VCC = 5.0 V ± 10%, CL = 50 pF, Input tr = tf = 6.0 ns)
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _{Guaranteed Limit}
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _Symbol
Parameter
– 55 to
25_C
v v 85_C
125_C Unit
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ tPLH,
tPHL
Maximum Propagation Delay, Input A or B to Output Y
(Figures 1 and 4)
27
34
41
ns
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _tPLH,
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _tPHL
Maximum Propagation Delay, Select to Output Y
(Figures 2 and 4)
37
46
56
ns
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _tPLH,
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ tPHL
Maximum Propagation Delay, Output Enable to Output Y
(Figures 3 and 4)
30
38
45
ns
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ tTLH,
tTHL
Maximum Output Transition Time, Any Output
(Figures 1 and 4)
15
19
22
ns
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _{tr, tf}
Maximum Input Rise and Fall Time
500
500
500
ns
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ _{NOTE:For propagation delays with loads other than 50 pF, and information on typical parametric values, see Chapter 2 of the Motorola High–}
Speed CMOS Data Book (DL129/D).
Typical @ 25°C, VCC = 5.0 V
CPD
Power Dissipation Capacitance (Per Transceiver Channel)*
64
pF
* Used to determine the no–load dynamic power consumption: PD = CPD VCC2f + ICC VCC. For load considerations, see Chapter 2 of the
Motorola High–Speed CMOS Data Book (DL129/D).
PIN DESCRIPTIONS
INPUTS
A0, A1, A2, A3 (Pins 2, 5, 11, 14)
Nibble A inputs. The data present on these pins is trans-
ferred to the outputs when the Select input is at a low level
and the Output Enable input is at a low level. The data is
presented to the outputs in noninverted form.
B0, B1, B2, B3 (Pins 3, 6, 10, 13)
Nibble B inputs. The data present on these pins is trans-
ferred to the outputs when the Select input is at a high level
and the Output Enable input is at a low level. The data is
presented to the outputs in noninverted form.
OUTPUTS
Y0, Y1, Y2, Y3 (Pins 4, 7, 9, 12)
Data outputs. The selected input Nibble is presented at
these outputs when the Output Enable input is at a low level.
The data is presented to the outputs in noninverted form. For
the Output Enable input at a high level, the outputs are at a
low level.
CONTROL INPUTS
Select (Pin 1)
Nibble select. This input determines the data word to be
transferred to the outputs. A low level on this input selects
the A inputs and a high level selects the B inputs.
Output Enable (Pin 15)
Output Enable input. A low level on this input allows the
selected input data to be presented at the outputs. A high
level on this input sets all outputs to a low level.
High–Speed CMOS Logic Data
3
DL129 — Rev 6
MOTOROLA