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74ABT16646
Skew
(SOIC Package)
Note 13: This specification is guaranteed but not tested. The limits apply to propagation delays for all paths described switching in phase
(i.e., all LOW-to-HIGH, HIGH-to-LOW, etc.).
Note 14: This specification is guaranteed but not tested. The limits represent propagation delays with 250 pF load capacitors in place of the 50 pF load
capacitors in the standard AC load.
Note 15: Skew is defined as the absolute value of the difference between the actual propagation delays for any two separate outputs of the same device.
The specification applies to any outputs switching HIGH to LOW (t
OSHL
), LOW to HIGH (t
OSLH
), or any combination switching LOW to HIGH and/or HIGH to
LOW (t
OST
). This specification is guaranteed but not tested.
Note 16: This describes the difference between the delay of the LOW-to-HIGH and the HIGH-to-LOW transition on the same pin. It is measured across all
the outputs (drivers) on the same chip, the worst (largest delta) number is the guaranteed specification. This specification is guaranteed but not tested.
Note 17: Propagation delay variation for a given set of conditions (i.e., temperature and V
CC
) from device to device. This specification is guaranteed but not
tested.
Capacitance
Note 18: C
I/O
is measured at frequency, f = 1 MHz, per MIL-STD-883, Method 3012.
Symbol Parameter
T
A
= −40°C to +85°CT
A
= −40°C to +85°C
Units
V
CC
= 4.5V–5.5V V
CC
= 4.5V–5.5V
C
L
= 50 pF C
L
= 250 pF
16 Outputs Switching 16 Outputs Switching
(Note 13) (Note 14)
Max Max
t
OSHL
Pin to Pin Skew
2.0 2.5 ns
(Note 15) HL Transitions
t
OSLH
Pin to Pin Skew
2.0 2.5 ns
(Note 15) LH Transitions
t
PS
Duty Cycle
2.0 2.5
(Note 16) LH–HL Skew
t
OST
Pin to Pin Skew
2.8 3.0 ns
(Note 15) LH/HL Transitions
t
PV
Device to Device Skew
3.5 4.0 ns
(Note 17) LH/HL Transitions
Symbol Parameter Typ Units
Conditions
T
A
= 25°C
C
IN
Input Capacitance 5 pF V
CC
= 0V (non I/O pins)
C
I/O
(Note 18) Output Capacitance 11 pF V
CC
= 5.0V (A
n
, B
n
)
