The MAX3070E-MAX3079E are 3.3V ±15kV ESD-protected RS-485/RS-422 transceivers with one driver and one receiver. They include fail-safe circuitry that guarantees a logic-high receiver output when receiver inputs are open or shorted. The receiver outputs a logic high if all transmitters on a terminated bus are disabled (high impedance). They also feature hot-swap capability to eliminate false transitions on the bus during power-up or hot insertion. The MAX3070E/MAX3071E/MAX3072E have reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX3073E/MAX3074E/MAX3075E also have slew-rate-limited drivers but allow transmit speeds up to 500kbps. The MAX3076E/MAX3077E/MAX3078E driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX3079E slew rate is pin selectable for 250kbps, 500kbps, and 16Mbps. The MAX3072E/MAX3075E/MAX3078E are intended for half-duplex communications, and the MAX3070E/MAX3071E/MAX3073E/MAX3074E/MAX3076E/MAX3077E are intended for full-duplex communications. The MAX3079E is selectable for half-duplex or full-duplex operation. It also features independently programmable receiver and transmitter output phase through separate pins. The MAX3070E-MAX3079E transceivers draw 800µA of supply current when unloaded or when fully loaded with the drivers disabled.
The MAX3070E‑MAX3079E family provides 3.3 V, +15 kV ESD‑protected RS‑485/RS‑422 transceivers with one driver and one receiver per device. Features include fail‑safe receiver operation, hot‑swap input structure, and selectable full‑ or half‑duplex modes (MAX3079E). The devices support a range of data rates from 250 kbps up to 16 Mbps depending on the specific part.
Typical applications are lighting systems, industrial control, telecom, security systems and instrumentation. The parts are offered in standard 8‑pin SO and 14‑pin DIP packages, with both leaded and lead‑free options. Absolute maximum ratings, electrical characteristics, and switching parameters are fully documented for design reference.
| Operating Voltage | 3.3 V |
|---|---|
| ESD Protection | +15 kV Human Body Model |
| Fail‑Safe Receiver | True fail‑safe receiver while maintaining EIA/TIA‑485 compatibility |
| Hot‑Swap Capability | Hot‑Swap input structure on DE and RE |
| Supply Current (no load) | 0.8 mA |
They provide +15 kV Human Body Model ESD protection on the RS‑485 I/O pins.
They operate from a 3.3 V supply.