MC145406
1
MOTOROLA
C0068C0114C0105C0118C0101C0114C0047C0082C0101C0099C0101C0105C0118C0101C0114
EIA 232–E and CCITT V.28 (Formerly RS–232–D)
The MC145406 is a silicon–gate CMOS IC that combines three drivers
and three receivers to fulfill the electrical specifications of standards
EIA 232–E and CCITT V.28. The drivers feature true TTL input
compatibility, slew–rate–limited output, 300–Ω power–off source imped-
ance, and output typically switching to within 25% of the supply rails. The
receivers can handle up to ±25 V while presenting 3 to 7 kΩ impedance.
Hysteresis in the receivers aids reception of noisy signals. By combining
both drivers and receivers in a single CMOS chip, the MC145406 provides
efficient, low–power solutions for EIA 232–E and V.28 applications.
Drivers
•± 5 V to ±12 V Supply Range
• 300–Ω Power–Off Source Impedance
• Output Current Limiting
• TTL Compatible
• Maximum Slew Rate = 30 V/µs
Receivers
•± 25 V Input Voltage Range When V
DD
= 12 V, V
SS
= – 12 V
• 3 to 7 kΩ Input Impedance
• Hysteresis on Input Switchpoint
BLOCK DIAGRAM
V
DD
RECEIVER
V
CC
DO
DI
1.4 V
HYSTERESIS
1.8 V
1.0 V
DRIVER
LEVEL
SHIFT
300 Ω
Tx
V
SS
5.4 k
Rx
15 kΩ
*Protection circuit
V
CC
V
DD
V
DD
V
CC
V
SS
+
–
+
–
*
Order this document
by MC145406/D
C0077C0079C0084C0079C0082C0079C0076C0065
SEMICONDUCTOR TECHNICAL DATA
PIN ASSIGNMENT
C0077C0067C0049C0052C0053C0052C0048C0054
P SUFFIX
PLASTIC
CASE 648
DW SUFFIX
SOG
CASE 751G
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
R
D
V
DD
Rx1
Tx1
Rx2
Tx2
Rx3
Tx3
V
SS
V
CC
DO1
DI1
DO2
DI2
DO3
DI3
GND
D = DRIVER
R = RECEIVER
R
R
D
D
16
1
16
1
SD SUFFIX
SSOP
CASE 940B
 Motorola, Inc. 1995
REV 4
1/95