The MAX3291/MAX3292 are high-speed RS-485/RS-422 transceivers with preemphasis circuitry, suitable for long-distance communication. The data rates are programmable from 5Mbps to 10Mbps for MAX3291, and up to 10Mbps with a single external resistor for MAX3292. These devices are full-duplex, operate from a single +5V supply, and offer a low-current shutdown mode. They feature driver output short-circuit current limiting and a fail-safe receiver input that guarantees a logic-high output if the input is open circuit. A 1/4-unit-load receiver input impedance allows up to 128 transceivers on the bus.
The MAX3291 and MAX3292 are full‑duplex RS‑485/RS‑422 transceivers that operate from a single +5 V supply. They feature driver pre‑emphasis circuitry to extend communication distance and increase data rates, while providing low‑current shutdown (100 nA) and short‑circuit protection.
The devices support data rates from 5 Mbps up to 10 Mbps, allow up to 128 transceivers on a single bus, and operate over a common‑mode input range of –7 V to +12 V. Pin‑compatible packages include 14‑lead SOIC and plastic DIP options, with detailed electrical characteristics and timing diagrams provided in the sheet.
| Data Rate (MAX3291) | 5 Mbps to 10 Mbps |
|---|---|
| Data Rate (MAX3292) | up to 10 Mbps |
| Common‑Mode Input Voltage Range | -7 V to +12 V |
| Shutdown Current (Low‑Current Mode) | 100 nA |
| Maximum Transceivers on Bus | 128 |
| Package Options | 14‑lead SOIC (MAX3291CSD) and 14‑lead Plastic DIP (MAX3291CPD) |
The MAX3291 supports data rates from 5 Mbps up to 10 Mbps.
Up to 128 transceivers can be connected on the bus.
The device draws only 100 nA in shutdown mode.