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74HC_HCT251_15 Datasheet, PDF (9/20 Pages) NXP Semiconductors – 8-input multiplexer; 3-state
NXP Semiconductors
74HC251; 74HCT251
8-input multiplexer; 3-state
Table 7. Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); CL = 50 pF unless otherwise specified; for test circuit, see Figure 10.
Symbol Parameter Conditions
Tamb = 25 C
Tamb = 40 C
to +85 C
Tamb = 40 C Unit
to +125 C
Min Typ Max Min
Max
Min
Max
74HCT251
tpd
propagation In to Y; see Figure 7
delay
VCC = 4.5 V
[1]
-
22 35
-
44
-
53 ns
VCC = 5 V; CL = 15 pF
-
19
-
-
-
-
- ns
In to Y; see Figure 7
[1]
VCC = 4.5 V
-
22 35
-
44
-
53 ns
VCC = 5 V; CL = 15 pF
-
19
-
-
-
-
- ns
Sn to Y; see Figure 8
[1]
VCC = 4.5 V
-
24 44
-
55
-
66 ns
VCC = 5 V; CL = 15 pF
-
20
-
-
-
-
- ns
Sn to Y; see Figure 8
[1]
VCC = 4.5 V
-
25 44
-
55
-
66 ns
VCC = 5 V; CL = 15 pF
-
21
-
-
-
-
- ns
ten
enable time OE to Y, Y; see Figure 8
[2]
VCC = 4.5 V
-
13 28
-
35
-
42 ns
VCC = 5 V; CL = 15 pF
-
13
-
-
-
-
- ns
tdis
disable time OE to Y, Y; see Figure 8
[3]
VCC = 4.5 V
-
14 28
-
35
-
42 ns
VCC = 5 V; CL = 15 pF
-
18
-
-
-
-
- ns
tt
transition Y, Y; see Figure 7
time
VCC = 4.5 V
[4]
-
7 15
-
19
-
22 ns
CPD
power
CL = 50 pF; f = 1 MHz;
[5] -
46 -
-
-
-
- pF
dissipation VI = GND to VCC
capacitance
[1] tpd is the same as tPLH and tPHL.
[2] ten is the same as tPZH and tPZL.
[3] tdis is the same as tPLZ and tPHZ.
[4] tt is the same as tTHL and tTLH.
[5] CPD is used to determine the dynamic power dissipation (PD in W).
PD = CPD  VCC2  fi  N + (CL  VCC2  fo) where:
fi = input frequency in MHz;
fo = output frequency in MHz;
CL = output load capacitance in pF;
VCC = supply voltage in V;
N = number of inputs switching;
(CL  VCC2  fo) = sum of outputs.
74HC_HCT251
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 9 July 2013
© NXP B.V. 2013. All rights reserved.
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