IC TXRX RS485 LOWPWR 8-MSOP

LTC1484CMS8

Manufacturer Part NumberLTC1484CMS8
DescriptionIC TXRX RS485 LOWPWR 8-MSOP
ManufacturerLinear Technology
TypeTransceiver
LTC1484CMS8 datasheet
 


Specifications of LTC1484CMS8

Number Of Drivers/receivers1/1ProtocolRS422, RS485
Voltage - Supply4.75 V ~ 5.25 VMounting TypeSurface Mount
Package / Case8-MSOP, Micro8™, 8-uMAX, 8-uSOP,Lead Free Status / RoHS StatusContains lead / RoHS non-compliant
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FEATURES
No Damage or Latchup to 15kV ESD (Human
Body Model), IEC-1000-4-2 Level 4 Contact ( 8kV)
and Level 3 ( 8kV) Air Gap Specifications
Guaranteed High Receiver Output State for Floating,
Shorted or Terminated Inputs with No Signal
Present
Drives Low Cost Residential Telephone Wires
Low Power: I
= 700 A Max with Driver Disabled
CC
I
= 900 A Max for Driver Enable with No Load
CC
20 A Max Quiescent Current in Shutdown Mode
Single 5V Supply
– 7V to 12V Common Mode Range Permits 7V
Ground Difference Between Devices on the Data Line
Power Up/Down Glitch-Free Driver Outputs
Up to 32 Transceivers on the Bus
Pin Compatible with the LTC485
Available in 8-Lead MSOP, PDIP and SO Packages
U
APPLICATIO S
Battery-Powered RS485/RS422 Applications
Low Power RS485/RS422 Transceiver
Level Translator
U
TYPICAL APPLICATIO
RS485 Interface
LTC1484
RO1
V
CC1
B1
R
RE1
120
A1
DE1
D
DI1
GND1
DESCRIPTIO
®
The LTC
1484 is a low power RS485 compatible trans-
ceiver. In receiver mode, it offers a fail-safe feature which
guarantees a high receiver output state when the inputs
are left open, shorted together or terminated with no
signal present. No external components are required to
ensure the high receiver output state.
Both driver and receiver feature three-state outputs with
separate receiver and driver control pins. The driver
outputs maintain high impedance over the entire com-
mon mode range when three-stated. Excessive power
dissipation caused by bus contention or faults is pre-
vented by a thermal shutdown circuit that forces the
driver outputs into a high impedance state.
Enhanced ESD protection allows the LTC1484 to with-
stand 15kV (human body model), IEC-1000-4-2 level 4
( 8kV) contact and level 3 ( 8kV) air discharge ESD
without latchup or damage.
The LTC1484 is fully specified over the commercial and
industrial temperature ranges and is available in 8-lead
MSOP, PDIP and SO packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTC1484
V
RO2
CC2
B2
R
RE2
120
A2
DE2
D
DI2
GND2
1484 TA01
LTC1484
Low Power
RS485 Transceiver
with Receiver Fail-Safe
U
Driving a 2000 Foot STP Cable
Dl1
B2
A2
RO2
Dl1
DE1 = V
1484 TA01a
CC
Dl2 = 0
DE2 = 0
RE1 = RE2 = 0
1

LTC1484CMS8 Summary of contents

  • Page 1

    ... IEC-1000-4-2 level 4 ( 8kV) contact and level 3 ( 8kV) air discharge ESD without latchup or damage. The LTC1484 is fully specified over the commercial and industrial temperature ranges and is available in 8-lead MSOP, PDIP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. LTC1484 V RO2 CC2 B2 ...

  • Page 2

    ... Junction Temperature .......................................... 125 C + 0.3V) Operating Temperature Range CC + 0.3V) LTC1484C ......................................... LTC1484I ...................................... – Storage Temperature Range ................. – 150 C + 0.3V) Lead Temperature (Soldering, 10 sec).................. 300 ORDER PART NUMBER RO 1 LTC1484CMS8 MS8 PART MARKING N8 PACKAGE 8-LEAD PDIP LTDX T = 125 C, JMAX T = 125 C, JMAX The denotes the specifications which apply over the full operating = 25 C ...

  • Page 3

    ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Receiver Input Hysteresis TH V Receiver Output High Voltage OH V Receiver Output Low Voltage OL I Three-State (High Impedance) Output Current OZR at Receiver R Receiver Input ...

  • Page 4

    LTC1484 U SWITCHING CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER t Driver Enable from Shutdown to Output High ZH(SHDN) t Driver Enable from Shutdown to Output Low ZL(SHDN) t Receiver Enable from Shutdown to Output High ZH(SHDN) ...

  • Page 5

    W U TYPICAL PERFOR A CE CHARACTERISTICS Receiver Input Offset Voltage vs Temperature –20 –40 –60 –80 –100 V = –7V CM –120 –140 V = 12V CM –160 –180 –200 ...

  • Page 6

    LTC1484 W U TYPICAL PERFOR A CE CHARACTERISTICS Receiver Short-Circuit Current vs Temperature 100 V = 5.25V OUTPUT LOW 60 SHORT OUTPUT HIGH 20 SHORT TO GROUND 10 0 –55 ...

  • Page 7

    W U TYPICAL PERFOR A CE CHARACTERISTICS Driver Differential Output Voltage vs Temperature 3 2.5 2 5.25V 1 4.75V 4.5V 1.0 CC 0.5 V ...

  • Page 8

    LTC1484 W U TYPICAL PERFOR A CE CHARACTERISTICS Driver Output High Voltage vs Output Current 5 4.75V CC 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 –100 –90 –80 –70 –60 –50 –40 –30 –20 –10 ...

  • Page 9

    PIN FUNCTIONS A (Pin 6): Driver Output/Receiver Input. The input resis- tance is typically 22k when the driver is disabled (DE = 0). When the driver is enabled, the A output follows the logic level at the ...

  • Page 10

    LTC1484 U W SWITCHI WAVEFOR 1. 90% 10% – 1 NOTE 1. 2.3V ...

  • Page 11

    U W SWITCHI WAVEFOR DZR V(A) – V(B) RO NOTE AND B ARE THREE-STATED WHEN APPLICATIONS INFORMATION Low Power ...

  • Page 12

    LTC1484 U U APPLICATIONS INFORMATION Shutdown Mode The receiver output (RO) and the driver outputs (A, B) can be three-stated by taking the RE and DE pins high and low respectively. Taking RE high and DE low at the same ...

  • Page 13

    U U APPLICATIONS INFORMATION 5V 5V 1.2k 120 8 5V 1.2k 1k receiver output and expects to see perfect agreement between the two data streams. (Note that the driver inverts the data, so the transmitted and received data streams are ...

  • Page 14

    LTC1484 U U APPLICATIONS INFORMATION longer delay for the falling edge is due to the larger voltage range the line must swing (typically > 2V compared to 370mV) before the receiver trips high again. The differ- ence in delay affects ...

  • Page 15

    ... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

  • Page 16

    ... Highest Input Impedance, Low EMI, Lowest Power 2500V Propagation Delay Skew 500ps (Typ) Low Power, 15kV ESD Protection “A” “B” 1484 TA02 Isolation RMS 15kV ESD Protection, Industry Standard Pinout 1484f LT/TP 0400 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 ...