|
|
PDF ADM2481 Data sheet ( Hoja de datos )
| Número de pieza | ADM2481 | |
| Descripción | Isolated RS-485 Transceiver | |
| Fabricantes | Analog Devices | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de ADM2481 (archivo pdf) en la parte inferior de esta página. Total 21 Páginas | ||
|
No Preview Available !
Data Sheet
FEATURES
RS-485 transceiver with electrical data isolation
Complies with ANSI TIA/EIA-485-A and ISO 8482: 1987(E)
500 kbps data rate
Slew rate-limited driver outputs
Low power operation: 2.5 mA maximum
Suitable for 5 V or 3.3 V operations (VDD1)
High common-mode transient immunity: >25 kV/μs
True fail-safe receiver inputs
Chatter-free power-up/power-down protection
256 nodes on bus
Thermal shutdown protection
Safety and regulatory approvals
UL recognition: 2500 V rms for 1 minute per
UL 1577
VDE certificates of conformity
DIN V VDE V 0884-10 (VDE V 0884-10): 2006-12
VIORM = 560 V peak
Operating temperature range: −40°C to +85°C
APPLICATIONS
Low power RS-485/RS-422 networks
Isolated interfaces
Building control networks
Multipoint data transmission systems
GENERAL DESCRIPTION
The ADM2481 differential bus transceiver is an integrated,
galvanically isolated component designed for bidirectional data
communication on balanced, multipoint bus transmission lines.
It complies with ANSI EIA/TIA-485-A and ISO 8482: 1987(E).
Using iCoupler® technology from Analog Devices, Inc., the
ADM2481 combines a 3-channel isolator, a three-state diffe-
rential line driver, and a differential input receiver into a single
package. The logic side of the device is powered with either a
5 V or 3 V supply, and the bus side uses a 5 V supply only.
The ADM2481 is slew-limited to reduce reflections with improp-
erly terminated transmission lines. The controlled slew rate
limits the data rate to 500 kbps. The input impedance of the
device is 96 kΩ, allowing up to 256 transceivers on the bus. Its
driver has an active-high enable feature. The driver differential
outputs and receiver differential inputs are connected internally
Half-Duplex, iCoupler
Isolated RS-485 Transceiver
ADM2481
FUNCTIONAL BLOCK DIAGRAM
VDD1
VDD2
ADM2481
DE
TxD
RxD
RE
GND1
GND2
Figure 1.
A
B
to form a differential I/O port. When the driver is disabled or
when VDD1 or VDD2 = 0 V, this imposes minimal loading on
the bus. An active-high receiver disable feature, which causes
the receiver output to enter a high impedance state, is provided
as well.
The receiver inputs have a true fail-safe feature that ensures a
logic-high receiver output level when the inputs are open or
shorted. This guarantees that the receiver outputs are in a
known state before communication begins and at the point
when communication ends.
Current limiting and thermal shutdown features protect against
output short circuits and bus contention situations that might
cause excessive power dissipation. The part is fully specified
over the industrial temperature range of −40°C to +85°C and is
available in a 16-lead, wide body SOIC package.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibilityisassumedbyAnalogDevices for itsuse,nor foranyinfringementsofpatentsor other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarksandregisteredtrademarksarethepropertyoftheirrespectiveowners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2010–2012 Analog Devices, Inc. All rights reserved.
1 page  
ADM2481
Data Sheet
TIMING SPECIFICATIONS
3.0 V ≤ VDD1 ≤ 5.5 V, 4.75 V ≤ VDD2 ≤ 5.25 V, TA = TMIN to TMAX, unless otherwise noted.
Table 2.
Parameter
DRIVER
Maximum Data Rate
Propagation Delay
Skew
Rise/Fall Time
Enable Time
Disable Time
RECEIVER
Propagation Delay
Differential Skew
Enable Time
Disable Time
Symbol
tPLH, tPHL
tSKEW
tR, tF
tPLH, tPHL
tSKEW
Min Typ Max Unit
500 kbps
250 620 ns
40 ns
200 600 ns
1050 ns
1050 ns
400
25
40
1050
250
70
70
ns
ns
ns
ns
Test Conditions/Comments
RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 18 and Figure 22
RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 18 and Figure 22
RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 18 and Figure 22
RL = 500 Ω, CL = 100 pF, see Figure 19 and Figure 24
RL = 500 Ω, CL = 15 pF, see Figure 19 and Figure 24
CL = 15 pF, see Figure 20 and Figure 23
CL = 15 pF, see Figure 20 and Figure 23
RL = 1 kΩ, CL = 15 pF, see Figure 21 and Figure 25
RL = 1 kΩ, CL = 15 pF, see Figure 21 and Figure 25
PACKAGE CHARACTERISTICS
Table 3.
Parameter
Resistance (Input-Output)1
Capacitance (Input-Output)1
Input Capacitance2
Symbol
RI-O
CI-O
CI
Min Typ
1012
3
4
Max Unit
Ω
pF
pF
Test Conditions
f = 1 MHz
1 Device is considered a 2-terminal device: Pin 1 to Pin 8 are shorted together, and Pin 9 to Pin16 are shorted together.
2 Input capacitance is from any input data pin to ground.
REGULATORY INFORMATION
Table 4. ADM2481 Approvals
Organization Approval Type
UL Recognized under the Component Recognition
Program of Underwriters Laboratories, Inc.
VDE Certified according to DIN V VDE V 0884-10
(VDE V 0884-10): 2006-12
Notes
In accordance with UL 1577, each ADM2481 is proof tested by
applying an insulation test voltage of ≥ 3000 V rms for 1 second
(current leakage detection limit = 5 µA).
In accordance with DIN V VDE V 0884-10, each ADM2481 is proof
tested by applying an insulation test voltage of ≥ 1050 V peak for
1 second (partial discharge detection limit = 5 pC).
INSULATION AND SAFETY-RELATED SPECIFICATIONS
Table 5.
Parameter
Rated Dielectric Insulation Voltage
Minimum External Air Gap (Clearance)
Symbol
L(I01)
Value
2500
7.7
Minimum External Tracking (Creepage)
L(I02)
7.6
Minimum Internal Gap (Internal Clearance)
Tracking Resistance (Comparative Tracking Index)
Isolation Group
CTI
0.017 min
>175
IIIa
Unit
V rms
mm
mm
mm
V
Conditions
1-minute duration
Measured from input terminals to output
terminals, shortest distance through air
Measured from input terminals to output
terminals, shortest distance along body
Insulation distance through insulation
DIN IEC 112/VDE 0303 Part 1
Material Group (Table 1 in DIN VDE 0110,1/89)
Rev. A | Page 4 of 20
5 Page 
ADM2481
350
300
250
BUS SIDE
200
150
LOGIC SIDE
100
50
0
0 50 100 150 200
CASE TEMPERATURE (°C)
Figure 13. Thermal Derating Curve, Dependence of Safety-Limiting Values
with Case Temperature per VDE 0884
35
30
25
20
15
10
5
0
0 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25
OUTPUT VOLTAGE (V)
Figure 14. Output Current vs. Receiver Output Low Voltage
Data Sheet
0
–5
–10
–15
–20
–25
–30
3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0
OUTPUT VOLTAGE (V)
Figure 15. Output Current vs. Receiver Output High Voltage
Rev. A | Page 10 of 20
11 Page | ||
| Páginas | Total 21 Páginas | |
| PDF Descargar | [ Datasheet ADM2481.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| ADM2481 | Isolated RS-485 Transceiver | Analog Devices |
| ADM2482E | 2.5 kV Isolated RS-485 Transceivers | Analog Devices |
| ADM2483 | Half-Duplex iCoupler Isolated RS-485 Transceiver | Analog Devices |
| ADM2484E | Isolated RS-485 Transceiver | Analog Devices |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |