FN7529.1 March 14, 2013 Application Information RS-485 and RS-422 are differential (balanced) data transmission standards for use in long haul " />
參數(shù)資料
型號: ISL32277EIRZ-T
廠商: Intersil
文件頁數(shù): 3/22頁
文件大小: 0K
描述: IC RCVR RS485/422 QD ESD 24QFN
產(chǎn)品培訓(xùn)模塊: Solutions for Industrial Control Applications
標(biāo)準(zhǔn)包裝: 6,000
類型: 接收器
驅(qū)動器/接收器數(shù): 0/4
規(guī)程: RS422,RS485
電源電壓: 3 V ~ 5.5 V
安裝類型: 表面貼裝
封裝/外殼: 24-VFQFN 裸露焊盤
供應(yīng)商設(shè)備封裝: 24-QFN 裸露焊盤(4x4)
包裝: 帶卷 (TR)
11
FN7529.1
March 14, 2013
Application Information
RS-485 and RS-422 are differential (balanced) data
transmission standards for use in long haul or noisy
environments. RS-422 is a subset of RS-485, so RS-485
transceivers are also RS-422 compliant. RS-422 is a
point-to-multipoint (multidrop) standard, which allows
only one driver and up to 10 (assuming one unit load
devices) receivers on each bus. RS-485 is a true
multipoint standard, which allows up to 32 one unit load
devices (any combination of drivers and receivers) on
each bus.
Another important advantage of RS-485 is the extended
common mode range (CMR), which specifies that the
driver outputs and receiver inputs withstand signals that
range from +12V to -7V. RS-422 and RS-485 are
intended for runs as long as 4000’, so the wide CMR is
necessary to handle ground potential differences, as well
as voltages induced in the cable by external fields.
Receiver Features
These devices utilize differential receivers for maximum
noise immunity and common mode rejection. Input
sensitivity is better than ±200mV, as required by the
RS-422 and RS-485 specifications.
Receiver input resistance of 48kΩ surpasses the RS-422
specification of 4kΩ and is four times the RS-485 “Unit
Load (UL)” requirement of 12kΩ minimum. Thus, these
products are known as “one-quarter UL” receivers and
there can be up to 128 of these devices on a network
while still complying with the RS-485 loading
specification.
Receiver inputs function with common mode voltages as
great as +9V/-7V outside the power supplies (i.e., +12V
and -7V with VCC = 3.0V), making them ideal for long
networks where induced voltages, and ground potential
differences are realistic concerns.
All the receivers include a “fail-safe open” function that
guarantees a high level receiver output if the receiver
inputs are unconnected (floating).
All receivers easily support a 20Mbps data rate, and the
ISL32173E, ISL32175E, and ISL32177E support data
rates up to 80Mbps. All receiver outputs are tri-statable,
with the enable scheme varying by part type (see next
section).
Receiver Enable Functions
All product types include functionality to allow disabling
of the Rx outputs. The ISL32X73E types feature group
(all four Rx) enable functions that are active high (EN) or
active low (EN). Receivers enable when EN = 1, or when
EN = 0, and they disable only when EN = 0 and EN = 1.
ISL32X75E versions use active high paired enable
Test Circuits and Waveforms
FIGURE 1A. TEST CIRCUIT
FIGURE 1B. MEASUREMENT POINTS
FIGURE 1. RECEIVER PROPAGATION DELAY
FIGURE 2A. TEST CIRCUIT
FIGURE 2B. MEASUREMENT POINTS
FIGURE 2. RECEIVER ENABLE AND DISABLE TIMES
SIGNAL
GENERATOR
R
RO
EN
A
B
+1.5V
15pF
RO
3V
0V
tPLH
1.5V
VCC OR VL
0V
50%
tPHL
A
50%
1kΩ
VCC
GND
SW
PARAMETER
A
SW
tHZ
+1.5V
GND
tLZ
-1.5V
VCC
tZH (Notes 15, 21)
+1.5V
GND
tZL (Notes 15, 21)
-1.5V
VCC
tZH(SHDN) (Notes 16, 20)
+1.5V
GND
tZL(SHDN) (Notes 16, 20)
-1.5V
VCC
SIGNAL
GENERATOR
R
RO
EN
A
B
GND
15pF
OR VL
RO
3V OR VL
0V
1.5V
VOH
0V
VOH - 0.5V
tHZ
RO
VCC OR VL
VOL
VOL + 0.5V
tLZ
EN
OUTPUT LOW
tZL, tZL(SHDN)
tZH, tZH(SHDN)
LOWER OF
1.5V OR VL/2
OUTPUT HIGH
1.5V OR VL/2
ISL32173E, ISL32175E, ISL32177E, ISL32273E, ISL32275E, ISL32277E
相關(guān)PDF資料
PDF描述
IDT72V36100L7-5PF8 IC FIFO 64X36 7-5NS 128QFP
MS27466E17B26PA CONN RCPT 26POS WALL MT W/PINS
IDT72V36100L7-5BB8 IC FIFO 64X36 7-5NS 144BGA
CS3102A-22-63S CONN RCPT 12POS BOX MNT W/SCKT
IDT72T1875L5BBI IC FIFO 16384X18 2.5V 5NS 144BGA
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL3232E 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:QFN Packaged, 【15kV ESD Protected, +2.7V to +5.5V, 150nA, 250kbps, RS-232 Transmitters/Receivers
ISL3232EIRZ 功能描述:IC XMITTER/RCVR ESD RS232 16-QFN RoHS:是 類別:集成電路 (IC) >> 接口 - 驅(qū)動器,接收器,收發(fā)器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:發(fā)射器 驅(qū)動器/接收器數(shù):4/0 規(guī)程:RS422,RS485 電源電壓:4.75 V ~ 5.25 V 安裝類型:表面貼裝 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
ISL3232EIRZ-T 功能描述:IC XMITTER/RCVR ESD RS232 16-QFN RoHS:是 類別:集成電路 (IC) >> 接口 - 驅(qū)動器,接收器,收發(fā)器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:發(fā)射器 驅(qū)動器/接收器數(shù):4/0 規(guī)程:RS422,RS485 電源電壓:4.75 V ~ 5.25 V 安裝類型:表面貼裝 封裝/外殼:16-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:16-SOIC 包裝:帶卷 (TR)
ISL3232EIRZ-T7A 功能描述:RS-232接口集成電路 3V RS-232 2TX/2RX -4 0+85 TRANS 16LD 5X5 RoHS:否 制造商:Exar 數(shù)據(jù)速率:52 Mbps 工作電源電壓:5 V 電源電流:300 mA 工作溫度范圍:- 40 C to + 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:LQFP-100 封裝:
ISL32372E 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:QUAD, ±16.5kV ESD Protected, 3.0V to 5.5V, Low Power, RS-422 Transmitters