ST26C31B
CMOS quad 3-state differential line driver
Features
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TTL input compatible
Typical propagation delay: 6 ns
Typical output skew: 0.5 ns
Output will not load line when V
CC
= 0 V
Meets the requirements of EIA standard
RS-422
Operation from single 5 V supply
3-state outputs for connection to system buses
Low quiescent current
Available in surface mount
TSSOP16
DIP-16
SO-16
Description
The ST26C31B is a quad differential line driver
designed for digital data transmission over
balanced lines and meets all the requirements of
EIA standard RS-422 while retaining the low
power characteristics of CMOS.
The ST26C31B accepts TTL or CMOS input
levels and translates these to RS-422 output
levels. This part uses special outputs circuitry
common to all four drivers. All outputs are
protected against damage due to electrostatic
discharge by diode to V
CC
and ground.
Table 1.
Device summary
Temperature range
-40 to 85 °C
-40 to 85 °C
-40 to 85 °C
Package
DIP-16
SO-16 (tape and reel)
TSSOP16 (tape and reel)
Packaging
25 parts per tube / 40 tube per box
2500 parts per reel
2500 parts per reel
Order codes
ST26C31BN
ST26C31BDR
ST26C31BTR
June 2008
Rev 8
1/15
www.st.com
15
Contents
ST26C31B
Contents
1
2
3
4
5
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2/15
ST26C31B
Pin configuration
1
Figure 1.
Pin configuration
Pin connections
Table 2.
Pin n°
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Pin description
Symbol
A
IN
A
OUT
A
OUT
EN
B
OUT
B
OUT
B
IN
GND
C
IN
C
OUT
C
OUT
EN
D
OUT
D
OUT
D
IN
V
CC
Input A
Channel A output
Channel A output
ENABLE
Channel B output
Channel B output
Input B
Ground
Input C
Channel C output
Channel C output
ENABLE
Channel D output
Channel D output
Input D
Supply voltage
Name and function
3/15
Pin configuration
ST26C31B
Table 3.
Truth table
Enable
H
Input
X
L
Output
Z
L
H
Output
Z
H
L
Enable
L
All other combinations of enable inputs
H
Note:
L = Low voltage state
H = High logic state
X = Don’t care
Z = High impedance
4/15
ST26C31B
Maximum ratings
2
Table 4.
Symbol
V
CC
V
IN
V
OUT
I
IK
I
OUT
I
CC
T
STG
Maximum ratings
Absolute maximum ratings
(1) (2)
Parameter
Supply voltage
DC input voltage
DC output voltage (high or low state)
Clamp diode current
DC output current per pin
DC V
CC
or gnd current
Storage temperature range
Value
-0.5 to 7
-0.5 to (V
CC
+ 0.5)
-0.5 to 7
±
20
±
150
±
150
-65 to +150
Unit
V
V
V
mA
mA
mA
°C
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.
2. Unless otherwise specified, all voltage are referenced to ground. All currents into the device pins are positive; all currents
out of the device pins are negative.
Table 5.
Symbol
V
CC
V
IN
V
OUT
V
OUT
T
A
t
r
, t
f
Recommended operating conditions
Parameter
Supply voltage
DC input voltage
DC output voltage (high or low state)
DC output voltage (V
CC
= 0 V or high impedance)
Operating temperature range
Maximum enable input rise or fall times
Value
4.5 to 5.5
0 to V
CC
0 to V
CC
0 to 5
-40 to +85
500
Unit
V
V
V
V
°C
ns
5/15
