SN75LBC784
www.ti.com
SLLS187B − NOVEMBER 1994 − REVISED JUNE 2007
QUADRUPLE RS-423-B
DRIVER/RECEIVER
DW PACKAGE
(TOP VIEW)
FEATURES
D
Four Independent Drivers and Receivers
3A
3Z
BIAS
2Z
1
28
27
26
25
24
23
22
21
20
19
18
D
Driver Slew Rate Controlled by a Single
Resistor
2
BIAS
4A
2A
3
D
Fast Driver Transition Times Down to
1.5 µs and Receiver Transition Times of
20 ns Typ
BIAS
1Z
4
4Z
5
BIAS
1A
6
D
D
D
D
Internal Thermal-Overload Protection
V
R
7
SS
ws
GND
4B
V
RS-423-B Inputs and Outputs Designed to
Withstand 25 V
8
DD
1Y
1B
2Y
9
4Y
10
11
ESD Protection Exceeds 2000 V Per
MIL-STD-833C Method 3015
3B
3Y 12
3C 13
4C 14
17 2B
16 2C
15 1C
LinBICMOS Process Technology
DESCRIPTION
FUNCTION TABLE
The SN75LBC784 performs as four independent
RS-423-B driver/receiver pairs designed to interface data
terminal equipment (DTE) with data circuit-terminating
equipment (DCE) at rates up to 120 kbps and distances to
1.2 km. The SN75LBC784 provides an upgrade to the
RS-232 serial interface and can be backwards-compatible
with existing serial ports while offering the higher
performance required by new faster peripherals, such as
v.34 (v.fast) modems. The RS-232 standard, and
subsequent revisions, only supports data rates up to 20
kbps over about 15 meters of cable. For RS-423-B the data
rate is increased to 120 kbps and transmission distance to
1.2 km by reducing the maximum output signal swing,
increasing the driver output current, and reducing the
receiver input voltage thresholds.
INPUTS
B
OUTPUTS
C
Z
Y
A
H
L
H
L
L
H
L
L
L
H
H
H
H
L
H
H
L
H
L
L
L
H
L
L
L
H
H
?
?
?
?
H
L
H
L
L
L
H
H
H
H = high level, L = low level,
X = irrelevant, Z = high impedance (off)
? = indeterminate
The receivers consist of differential comparators with hysteresis and resistive attenuation on the inputs. The resistive attenuation
improves the input common-mode range and also provides additional protection from ESD and over-voltage stress. The differential
and common-mode input impedances are sufficiently high to meet RS-423-B. When a differential voltage input of 500 mV is applied
across the entire common-mode range (see Figure 5), the receiver characteristics and bias voltage allow the receiver to remain
in its intended binary state.
The drivers meet all RS-423-B specifications with built-in current limits and thermal overload protection. Slew-rate controlling
circuitry is included in the design, which is adjusted to suit the application by means of an external resistor (Rws). The slew rate
controlling circuitry also has a default mode—if the Rws pin is shorted to 5 V externally, the transistion time defaults to approximately
1.5 ms. The BIAS input, when shorted to 5 V externally, provides the internal node voltages. The receiver is compatible to RS-232
with the use of external input resistors to meet the RS-232 input resistance specification of 3 kΩ to 7 kΩ.
The SN75LBC784 is characterized for operation over the temperature range of 0°C to +70°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments
semiconductor products and disclaimers thereto appears at the end of this data sheet.
LinBiCMOS is a trademark of Texas Instruments Incorporated. All other trademarks are the property of their respective owners.
ꢀꢁ ꢂ ꢃꢄ ꢅ ꢆꢇ ꢂꢈ ꢃ ꢉꢆꢉ ꢊꢋ ꢌꢍ ꢎꢏ ꢐꢑꢊ ꢍꢋ ꢊꢒ ꢓꢔ ꢎ ꢎ ꢕꢋꢑ ꢐꢒ ꢍꢌ ꢖꢔꢗ ꢘꢊꢓ ꢐꢑꢊ ꢍꢋ ꢙꢐ ꢑꢕꢚ ꢀꢎ ꢍꢙꢔ ꢓꢑꢒ
ꢓ ꢍꢋ ꢌꢍꢎ ꢏ ꢑꢍ ꢒ ꢖꢕ ꢓ ꢊ ꢌꢊ ꢓ ꢐ ꢑꢊ ꢍꢋꢒ ꢖꢕ ꢎ ꢑꢛꢕ ꢑꢕ ꢎ ꢏꢒ ꢍꢌ ꢆꢕꢜ ꢐ ꢒ ꢇꢋꢒ ꢑꢎ ꢔꢏ ꢕꢋꢑ ꢒ ꢒꢑ ꢐꢋꢙ ꢐꢎ ꢙ ꢝ ꢐꢎ ꢎ ꢐ ꢋꢑꢞꢚ
ꢀꢎ ꢍ ꢙꢔꢓ ꢑ ꢊꢍ ꢋ ꢖꢎ ꢍ ꢓ ꢕ ꢒ ꢒ ꢊꢋ ꢟ ꢙꢍ ꢕꢒ ꢋꢍꢑ ꢋꢕ ꢓꢕ ꢒꢒ ꢐꢎ ꢊꢘ ꢞ ꢊꢋꢓ ꢘꢔꢙ ꢕ ꢑꢕ ꢒꢑꢊ ꢋꢟ ꢍꢌ ꢐꢘ ꢘ ꢖꢐ ꢎ ꢐꢏ ꢕꢑꢕ ꢎ ꢒꢚ
Copyright 1994−2007, Texas Instruments Incorporated
www.ti.com
5秒后页面跳转
摩尔斯微电子在美国约书亚树国家公园测试 Wi-Fi HaLow
贸泽上架Tallysman TW5386智能GNSS天线
SL74HC10N：高性能三输入与非门解析
AIC1781A 电池充电控制器深度解析
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
数据手册
如果您发现信息不准确，
