Intersil’s ISL3159E is a ±15kV IEC61000 ESD protected, 5V

powered, single transceiver that meets both the RS-485 and

RS-422 standards for balanced communication. It also

features the larger output voltage and higher data rate - up to

40Mbps - required by high speed PROFIBUS applications, and

is offered in industrial and extended Industrial (-40°C to

+125°C) temperature ranges. The low bus currents

(+220µA/-150µA) 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 load limit and without

using repeaters.

This transceiver requires a 5V ±10 tolerance supply, and

delivers at least a 2.1V differential output voltage over this

supply range. This translates into better noise immunity (data

integrity), longer reach, or the ability to drive up to six 120Ω

terminations in “star” or other nonstandard bus topologies, at

the exceptional 40Mbps data rate.

SCSI applications benefit from the ISL3159’s low receiver and

transmitter part-to-part skews, which make it perfect for high

speed parallel applications where large numbers of bits must

be simultaneously captured. The low bit-to-bit skew eases the

timing constraints on the data latching signal.

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. Rx outputs feature high

drive levels (typically >30mA at VOL = 1V) to ease the design of

optically isolated interfaces.

Hot plug circuitry ensures that the Tx and Rx outputs remain in

a high impedance state while the power supply stabilizes.

Driver (Tx) outputs are short-circuit protected, even for voltages

exceeding the power supply voltage. Additionally, on-chip

thermal shutdown circuitry disables the Tx outputs to prevent

damage if power dissipation becomes excessive.

Features

• IEC61000 ESD protection on RS-485 I/O Pins . . . . . . ±15kV

- Class 3 HBM ESD level on all other pins . . . . . . . . . . . >9kV

• Large differential VOUT . . . . . . . . . . . . . . . . . . . 2.8V into 54Ω

Better noise immunity, or drive up to 6 terminations

• High data rates. . . . . . . . . . . . . . . . . . . . . . . . . . up to 40Mbps

• Specified for +125°C operation

• 11/13ns (max) Tx/Rx propagation delays; 1.5ns (max) skew

• 1/5 unit load allows up to 160 devices on the bus

• Full fail-safe (open, shorted, terminated/undriven) receiver

• High Rx IOL to drive optocouplers for isolated applications

• Hot plug - Tx and Rx outputs remain three-state during

power-up

• Low quiescent supply current. . . . . . . . . . . . . . . . . . . . . . 4mA

• Low current shutdown mode . . . . . . . . . . . . . . . . . . . . . . . 1µA

• -7V to +12V common-mode input voltage range

• Three-state Rx and Tx outputs

• Operates from a single +5V supply (10 tolerance)

• Current limiting and thermal shutdown for driver overload

protection

• Pb-free (RoHS compliant)

Applications

• PROFIBUS DP and FMS networks

• SCSI “fast 40” drivers and receivers

• Motor controller/position encoder systems

• Factory automation

• Field bus networks

• Security networks

• Building environmental control systems

• Industrial/process control networks