74LVC_LVCH245A All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 8 — 28 June 2013 7 of 18
NXP Semiconductors
74LVC245A; 74LVCH245A
Octal bus transceiver; 3-state
10. Dynamic characteristics
[1] t
pd
is the same as t
PLH
and t
PHL
.
t
en
is the same as t
PZL
and t
PZH
.
t
dis
is the same as t
PLZ
and t
PHZ
.
[2] Typical values are measured at T
amb
=25C and V
CC
= 1.2 V, 1.8 V, 2.5 V, 2.7 V and 3.3 V respectively.
[3] Skew between any two outputs of the same package switching in the same direction. This parameter is guaranteed by design.
[4] C
PD
is used to determine the dynamic power dissipation (P
D
in W).
P
D
=C
PD
V
CC
2
f
i
N+(C
L
V
CC
2
f
o
) where:
f
i
= input frequency in MHz; f
o
= output frequency in MHz
C
L
= output load capacitance in pF
V
CC
= supply voltage in Volts
N = number of inputs switching
(C
L
V
CC
2
f
o
) = sum of the outputs.
Table 7. Dynamic characteristics
Voltages are referenced to GND (ground = 0 V). For test circuit see Figure 7.
Symbol Parameter Conditions 40 C to +85 C 40 C to +125 C Unit
Min Typ
[2]
Max Min Max
t
pd
propagation
delay
nAn to nBn; nBn to nAn; see Figure 5
[1]
V
CC
= 1.2 V - 17.0 - - - ns
V
CC
= 1.65 V to 1.95 V 1.5 6.5 14.6 1.5 16.9 ns
V
CC
= 2.3 V to 2.7 V 1.0 3.4 7.6 1.0 8.7 ns
V
CC
= 2.7 V 1.5 3.4 7.3 1.5 9.5 ns
V
CC
= 3.0 V to 3.6 V 1.5 2.9 6.3 1.5 8.0 ns
t
en
enable time nOE to nAn, nBn; see Figure 6
[1]
V
CC
= 1.2 V - 22.0 - - - ns
V
CC
= 1.65 V to 1.95 V 1.9 8.3 19.5 1.9 22.5 ns
V
CC
= 2.3 V to 2.7 V 1.5 4.6 10.7 1.5 12.4 ns
V
CC
= 2.7 V 1.5 4.8 9.5 1.5 12.0 ns
V
CC
= 3.0 V to 3.6 V 1.5 3.7 8.5 1.5 11.0 ns
t
dis
disable time nOE to nAn, nBn; see Figure 6
[1]
V
CC
= 1.2 V - 12.0 - - - ns
V
CC
= 1.65 V to 1.95 V 2.9 5.5 12.3 2.9 14.2 ns
V
CC
= 2.3 V to 2.7 V 1.0 3.1 7.1 1.0 8.2 ns
V
CC
= 2.7 V 1.5 3.9 8.0 1.5 10.0 ns
V
CC
= 3.0 V to 3.6 V 1.7 3.6 7.0 1.7 9.0 ns
t
sk(o)
output skew
time
[3]
- - 1.0 - 1.5 ns
C
PD
power
dissipation
capacitance
per input; V
I
=GNDtoV
CC
[4]
V
CC
= 1.65 V to 1.95 V - 7.7 - - - pF
V
CC
= 2.3 V to 2.7 V - 11.3 - - - pF
V
CC
= 3.0 V to 3.6 V - 14.4 - - - pF