DC Electrical Characteristics
Symbol
I
OFF
Parameter
Output Leakage Current
Power Off (Note 5)
(Continued)
V
CC
= 5V
±
10% (unless otherwise specified) (Note 4)
DS26C31T
V
CC
= 0V
DS26C31M
V
CC
= 0V
Conditions
V
OUT
= 6V
V
OUT
= −0.25V
V
OUT
= 6V
V
OUT
= 0V
(Note 8)
Note 1:
Absolute Maximum Ratings are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device
should be operated at these limits. The table of “Electrical Characteristics” provide conditions for actual device operation.
Note 2:
Unless otherwise specified, all voltages are referenced to ground. All currents into device pins are positive, all currents out of device pins are negative.
Note 3:
Ratings apply to ambient temperature at 25˚C. Above this temperature derate N package at 13.89 mW/˚C, J package 16.13 mW/˚C, M package 9.80 mW/˚C,
E package 12.20 mW/˚C, and W package 6.75 mW/˚C.
Note 4:
Unless otherwise specified, min/max limits apply across the recommended operating temperature range. All typicals are given for V
CC
= 5V and T
A
= 25˚C.
Note 5:
See EIA Specification RS-422 for exact test conditions.
Note 6:
Measured per input. All other inputs at V
CC
or GND.
Note 7:
This is the current sourced when a high output is shorted to ground. Only one output at a time should be shorted.
Note 8:
The DS26C31M (−55˚C to +125˚C) is tested with V
OUT
between +6V and 0V while RS-422A condition is +6V and −0.25V.
Min
Typ
Max
100
−100
100
−100
Units
µA
µA
µA
µA
Switching Characteristics
V
CC
= 5V
±
10%, t
r
≤
6 ns, t
f
≤
6 ns (Figures
1, 2, 3, 4)
(Note 4)
Symbol
t
PLH
, t
PHL
Skew
t
TLH
, t
THL
t
PZH
t
PZL
t
PHZ
t
PLZ
C
PD
C
IN
Parameter
Propagation Delays
Input to Output
(Note 9)
Differential Output Rise
And Fall Times
Output Enable Time
Output Enable Time
Output Disable Time
(Note 10)
Output Disable Time
(Note 10)
Power Dissipation
Capacitance (Note 11)
Input Capacitance
6
pF
Note 9:
Skew is defined as the difference in propagation delays between complementary outputs at the 50% point.
Note 10:
Output disable time is the delay from ENABLE or ENABLE being switched to the output transistors turning off. The actual disable times are less than in-
dicated due to the delay added by the RC time constant of the load.
Note 11:
C
PD
determines the no load dynamic power consumption, P
D
= C
PD
V
CC
2 f + I
CC
V
CC
, and the no load dynamic current consumption, I
S
= C
PD
V
CC
f +
I
CC
.
Conditions
S1 Open
S1 Open
S1 Open
S1 Closed
S1 Closed
S1 Closed
S1 Closed
Min
2
Typ
DS26C31T
6
0.5
6
11
13
5
7
50
11
2.0
10
19
21
9
11
Max
CS26C31M
14
3.0
14
22
28
12
14
Units
ns
ns
ns
ns
ns
ns
ns
pF
Comparison Table of Switching Characteristics into “LS-Type” Load
V
CC
= 5V, T
A
= 25˚C, t
r
≤
6 ns, t
f
≤
6 ns (Figures
2, 4, 5, 6)
(Note 12)
Symbol
t
PLH
, t
PHL
Parameter
Propagation Delays
Input to Output
Skew
(Note 9)
Conditions
C
L
= 30 pF
S1 Closed
S2 Closed
C
L
= 30 pF
S1 Closed
S2 Closed
0.5
1.0
2.0
6.0
ns
6
8
10
15
ns
DS26C31T
Typ
Max
DS26LS31C
Typ
Max
Units
3
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