- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄1898 > ADM2485BRWZ-REEL7 (Analog Devices Inc)IC TXRX ISOLATED RS-485 16SOIC PDF資料下載
參數(shù)資料
| 型號： | ADM2485BRWZ-REEL7 |
| 廠商： | Analog Devices Inc |
| 文件頁數(shù)： | 7/20頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC TXRX ISOLATED RS-485 16SOIC |
| 產(chǎn)品培訓(xùn)模塊： | iCoupler Digital Isolater Technology |
| 設(shè)計(jì)資源： | Half-Duplex, Isolated RS-485 Interface (CN0031) |
| 標(biāo)準(zhǔn)包裝： | 1 |
| 系列： | * |
| 其它名稱： | ADM2485BRWZ-REEL7DKR |
ADM2485
Rev. A | Page 15 of 20
MAGNETIC FIELD IMMUNITY
Because iCouplers use a coreless technology, no magnetic
components are present and the problem of magnetic saturation
of the core material does not exist. Therefore, iCouplers have
essentially infinite dc field immunity. The following analysis
defines the conditions under which this can occur. The ADM2485
3.3 V operating condition is examined because it represents the
most susceptible mode of operation.
The limitation on the iCoupler ac magnetic field immunity is
set by the condition in which the induced error voltage in the
receiving coil (the bottom coil, in this case) is made sufficiently
large, either to falsely set or reset the decoder. The voltage
induced across the bottom coil is given by
∑π
=
2
n
r
dt
dβ
V
; n = 1, 2 … N
(1)
where, if the pulses at the transformer output are greater than
1.0 V in amplitude:
β is the magnetic flux density (gauss).
N is the number of turns in the receiving coil.
rn is the radius of nth turn in the receiving coil (cm).
The decoder has a sensing threshold of about 0.5 V; therefore,
there is a 0.5 V margin where induced voltages can be tolerated.
Given the geometry of the receiving coil and an imposed
requirement that the induced voltage is, at most, 50% of the
0.5 V margin at the decoder, a maximum allowable magnetic
field is calculated, as shown in Figure 31.
MAGNETIC FIELD FREQUENCY (Hz)
1k
10k
100k
100M
1M
10M
100
10
1
0.1
0.01
0.001
MA
X
IMU
M
A
L
O
W
A
B
L
E
MA
G
N
E
T
IC
F
L
UX
DE
NS
IT
Y
(
kG
A
US
S
)
0
60
21
-02
7
Figure 31. Maximum Allowable External Magnetic Flux Density vs.
Magnetic Field Frequency
For example, at a magnetic field frequency of 1 MHz, the
maximum allowable magnetic field of 0.2 kGauss induces a
voltage of 0.25 V at the receiving coil, which is about 50% of the
sensing threshold and does not cause a faulty output transition.
Similarly, if such an event occurs during a transmitted pulse and
it is the worst-case polarity, it reduces the received pulse from
>1.0 V to 0.75 V, still well above the 0.5 V sensing threshold of
the decoder.
Figure 32 shows the magnetic flux density values in terms of
more familiar quantities, such as maximum allowable current
flow at given distances from the ADM2485 transformers.
MAGNETIC FIELD FREQUENCY (Hz)
1k
10k
100k
100M
1M
10M
DISTANCE = 1m
DISTANCE = 100mm
DISTANCE = 5mm
1000
100
0.1
0
10
0.01
M
A
X
IM
UM
AL
L
O
W
ABL
E
CURRE
NT
(
kA)
06
02
1-
02
8
Figure 32. Maximum Allowable Current for
Various Current-to-ADM2485 Spacings
At combinations of strong magnetic field and high frequency,
any loops formed by printed circuit board (PCB) traces could
induce sufficiently large error voltages to trigger the thresholds
of succeeding circuitry. Care must be taken in the layout of such
traces to avoid this possibility.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ADM2486BRW | IC TXRX RS-485 ISOLATED 16-SOIC |
| ADM2490EBRWZ | IC TXRX RS-485 ISOLATED 16-SOIC |
| ADM2491EBRWZ-REEL7 | IC TXRX HS ESD PROT ISO 16SOIC |
| ADM2587EBRWZ | IC TXRX RS485 ISOLATED 20SOIC |
| ADM3051CRZ | IC TXRX CAN 24V 1MBPS 8SOIC |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ADM2486 | 制造商:AD 制造商全稱:Analog Devices 功能描述:High Speed, Half-Duplex iCoupler Isolated RS-485 Transceiver |
| ADM2486BRW | 功能描述:IC TXRX RS-485 ISOLATED 16-SOIC RoHS:否 類別:集成電路 (IC) >> 接口 - 驅(qū)動器，接收器，收發(fā)器 系列:iCoupler® 標(biāo)準(zhǔn)包裝:250 系列:- 類型:收發(fā)器 驅(qū)動器/接收器數(shù):2/2 規(guī)程:RS232 電源電壓:3 V ~ 5.5 V 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應(yīng)商設(shè)備封裝:16-TSSOP 包裝:帶卷 (TR) |
| ADM2486BRW-REEL | 制造商:Analog Devices 功能描述:Single Transmitter/Receiver RS-485 16-Pin SOIC W T/R 制造商:Analog Devices 功能描述:LINE TRNSCVR 1TR 1TX 1RX 16SOIC W - Tape and Reel |
| ADM2486BRWZ | 功能描述:IC TXRX RS-485 ISOLATED 16-SOIC RoHS:是 類別:集成電路 (IC) >> 接口 - 驅(qū)動器，接收器，收發(fā)器 系列:iCoupler® 產(chǎn)品培訓(xùn)模塊:RS-232 & USB Transceiver 標(biāo)準(zhǔn)包裝:2,000 系列:- 類型:收發(fā)器 驅(qū)動器/接收器數(shù):1/1 規(guī)程:RS232 電源電壓:3 V ~ 5.5 V 安裝類型:表面貼裝 封裝/外殼:16-SSOP（0.209"，5.30mm 寬） 供應(yīng)商設(shè)備封裝:16-SSOP 包裝:帶卷 (TR) 其它名稱:296-19849-2 |
| ADM2486BRWZ-REEL | 功能描述:IC TXRX RS-485 ISOLATED 16SOIC RoHS:是 類別:集成電路 (IC) >> 接口 - 驅(qū)動器，接收器，收發(fā)器 系列:iCoupler® 標(biāo)準(zhǔn)包裝:27 系列:- 類型:收發(fā)器 驅(qū)動器/接收器數(shù):3/3 規(guī)程:RS232，RS485 電源電壓:4.75 V ~ 5.25 V 安裝類型:表面貼裝 封裝/外殼:28-SOIC（0.295"，7.50mm 寬） 供應(yīng)商設(shè)備封裝:28-SOIC 包裝:管件 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。