ISL3179E

High ESD Protected, +125°C, 40Mbps, 3.3V, Full Fail-Safe, RS-485/RS-422 Transceivers

Product Status: Mass Production

OVERVIEW

The ISL3179E and ISL3180E are high ESD protected, 3.3V powered, single transceivers that meet both the RS-485 and RS-422 standards for balanced communication. Each device has low bus currents (+220μA/-150μA), so they present a “1/5 unit load” to the RS-485 bus. This allows up to 160 transceivers on the network without violating the RS-485 specification’s 32 unit load maximum, and without using repeaters.

Receiver (Rx) inputs feature a “full fail-safe” design, which ensures a logic high Rx output if Rx inputs are floating, shorted, or terminated but undriven.

The ISL3180E is configured for full duplex applications. The ISL3179E half duplex version multiplexes the Rx inputs and Tx outputs to allow a transceiver with an output disable function in 8 Ld packages.

Hot plug circuitry ensures that the Tx and Rx outputs remain in a high impedance state while the power supply stabilizes.

KEY FEATURES

  • High ESD protection on RS-485 I/O pins
  • ISL3179E: ±16.5kV IEC61000
  • ISL3180E: ±12kV HBM
  • Class 3 HBM level on all other pins (ISL3179E): >9kV
  • Specified for +125°C operation
  • High data rates: up to 40Mbps
  • 5V tolerant logic inputs
  • 1/5 unit load allows up to 160 devices on the bus
  • Full fail-safe (open, shorted, terminated/undriven) receiver
  • Hot plug - Tx and Rx outputs remain three-state during power-up
  • Low quiescent current: 4mA (max)
  • Low current shutdown mode: 1μA (max)
  • -7V to +12V common-mode input voltage range
  • Three-state Rx and Tx outputs
  • 16/16.5ns (max) Tx/Rx propagation delays; 1.5ns (max) skew
  • Operates from a single +3.3V supply (10% tolerance)
  • Current limiting and thermal shutdown for driver overload protection
  • Pb-free (RoHS compliant)

BLOCK DIAGRAM

 Block Diagram

PARAMETRICS

Parameters
ISL3179E
Basic Information
Production Status
Mass Production
Key Feature
High Speed
# of Tx
1
# of Rx
1
Devices Allowed on Bus
160
Half/Full Duplex
Half
High ESD Protection
Yes-IEC61000
Hot Plug
Yes
Data Rate
40 Mbps
Supply Voltage Vcc (Min) (V)
3
Supply Voltage Vcc (Max) (V)
3.6
Slew Rate Limited
No
Tx/Rx Enable
Yes
IS Enabled/Disabled
2600/2600 µA
SHDN ICC
<1 μA
VL Pin
No
Qualification Level
Standard
Supply Voltage Vcc Range (V)
3.0 to 3.6
Can Sample
YES
Temperature Range
-40 to +125

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