Intersil RS-485/RS-422 devices are BiCMOS 5V powered, single transceivers that meet both the RS-485 and RS-422 standards for balanced communication. The devices feature slew rate limited drivers which reduce EMI, and minimize reflections from improperly terminated transmission lines, or unterminated stubs in multidrop and multipoint applications. Data rates up to 5Mbps are achievable by using the ISL8485, ISL8490, or ISL8491, which feature higher slew rates. All devices present a 'single unit load' to the RS-485 bus, which allows up to 32 transceivers on the network. Receiver (Rx) inputs feature a 'fail-safe if open' design, which ensures a logic high Rx output if Rx inputs are floating. 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.
The Intersil ISL8483‑ISL8491 family are 5 V BICMOS RS‑485/RS‑422 transceivers designed for 10 % tolerance supplies (4.5 V to 5.5 V). They offer low‑power operation, slew‑rate‑limited drivers for EMI reduction, and a single‑unit‑load that permits up to 32 devices on a bus.
The datasheet provides detailed electrical specifications, pin descriptions, typical operating circuits, ordering information, and package dimensions for both SOIC and PDIP variants. It also includes test circuits, waveform examples, and absolute maximum ratings.
| Supply voltage range | 4.5 V to 5.5 V (10 % tolerance) |
|---|---|
| Maximum data rate | up to 5 Mbps |
| Quiescent current (typical) | 160 µA (ISL8483, ISL8488, ISL8489) |
| ESD protection | Class 3, >7 kV (HBM) |
They can operate at data rates up to 5 Mbps.
They operate from 4.5 V to 5.5 V, a 10 % tolerance around the nominal 5 V.
Typical quiescent current is 160 µA for the ISL8483, ISL8488, and ISL8489 devices.