参数资料
| 型号： | MC75174BPG |
| 厂商： | ON Semiconductor |
| 文件页数： | 2/13页 |
| 文件大小： | 0K |
| 描述： | IC LINEDRVR QUAD EIA485 16-DIP |
| 产品变化通告： | Product Obsolescence 24/Jan/2011 |
| 标准包装： | 25 |
| 类型： | 线路驱动器，发射器 |
| 驱动器/接收器数： | 4/0 |
| 规程： | RS422，RS485 |
| 电源电压： | 4.75 V ~ 5.25 V |
| 安装类型： | 通孔 |
| 封装/外壳： | 16-DIP（0.300"，7.62mm） |
| 供应商设备封装： | 16-DIP |
| 包装： | 管件 |
MC75172B, MC75174B
http://onsemi.com
10
Termination Resistors
Transmission line theory states that, in order to preserve
the shape and integrity of a waveform traveling along a
cable, the cable must be terminated in an impedance equal
to its characteristic impedance. In a system such as that
depicted in Figure 18, in which data can travel in both
directions, both physical ends of the cable must be
terminated. Stubs, leading to each receiver and driver,
should be as short as possible.
Leaving off the terminations will generally result in
reflections which can have amplitudes of several volts
above VCC or below ground. These overshoots and
undershoots can disrupt the driver and/or receiver
operation, create false data, and in some cases damage
components on the bus.
Figure 18. Typical EIA485 System
NOTES:
1.Terminating resistors RT must be located at the physical ends of the cable.
2.Stubs should be as short as possible.
3.Circuit ground of all drivers and receivers must be connected via a dedicated wire within the cable.
Do not rely on chassis ground or power line ground.
#8
TTL
R
TTL
#3
TTL
R
En
#2
TTL
En
TTL
R
TTL
#1
R
TTL
RT
#1
En
D
#3
D
#5
D
TTL
En
#6
R
TTL
R
En
#5
R
#6
D
#7
RT
TTL
R
En
TTL
#4
D
5 “off” drivers (@ 0.06 U.L. each),
+8 receivers (@ 1.0 U.L. each) = 8.3 Unit Loads
RT = 120 W at each end of the cable.
#4
D
#2
120
W
Twisted
Pair
相关PDF资料 |
PDF描述 |
|---|---|
| MC75174BDWG | IC LINEDRVR QUAD EIA485 20-SOICW |
| VI-B3B-MY-S | CONVERTER MOD DC/DC 95V 50W |
| MC75172BDWG | IC LINEDRIVER QUAD 3ST 20-SOICW |
| VI-B3B-MW-S | CONVERTER MOD DC/DC 95V 100W |
| CY28446LFXCT | IC CLOCK CALISTOGA CK410M 64QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MC7520D | 制造商:POSITRONIC INDUSTRIES, INC. 功能描述: 制造商: 功能描述: 制造商:undefined 功能描述: |
| MC75368P | 制造商:Motorola Inc 功能描述: 制造商:MOTOROLA 功能描述: |
| MC75450P | 制造商:National Semiconductor 功能描述:75450 NSC'93 |
| MC75451P | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| MC75453P | 制造商:Motorola Inc 功能描述: 制造商:MOTOROLA 功能描述: |
发布紧急采购，3分钟左右您将得到回复。