Overview
Description
The ISL3259E is a ±15kV IEC 61000 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 100Mbps) required by high-speed PROFIBUS applications. 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 supply, and delivers at least a 2.1V differential output voltage. This translates into better noise immunity (data integrity), longer reach, or the ability to drive up to six 120Ω terminations in “star” or other non-standard bus topologies. SCSI applications benefit from the ISL3259E’s low receiver and transmitter part-to-part skews. The ISL3259E is perfect for high-speed parallel applications requiring simultaneous capture of large numbers of bits. 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
- IEC 61000 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
- Very high data rate: up to 100Mbps
- 11/13ns (maximum) Tx/Rx propagation delays; 1.5ns (maximum) 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 opto-couplers 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
- Current limiting and thermal shutdown for driver overload protection
- Pb-free (RoHS compliant)
Comparison
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
Design & Development
Models
ECAD Models
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.