MAX485CPA+

MAX485CPA+ is an 8-pin, low‑power RS‑485/RS‑422 transceiver from Maxim Integrated. It combines a driver and a receiver for half‑duplex, two‑wire RS‑485 networks, suitable for microcontroller interfaces.
Key points:
- Single-supply operation (typically 5 V) with data rates up to 2.5 Mbps.
- 1/8 unit load, supporting multi‑node (multi‑drop) networks on the A/B bus.
- DI (driver input), RO (receiver output), DE (driver enable), /RE (receiver enable) pins for precise direction control.
- Failsafe receiver outputs a valid logic high when the bus is idle, open, or shorted.
- Designed for robust industrial applications (industrial automation, building controls, sensors, etc.).
The “+” variant denotes the CPA+ packaging/offer from Maxim; consult the datasheet for exact temperature range, pinout, and packaging details.

Equivalent RS-485/RS-422 half‑duplex 5V transceivers (drop‑in style equivalents):
- TI: SN65HVD178 (and SN65HVD2x family)
- ST: SP3482 / SP3485
- NXP: PCA82C250 / PCA82C251
- Analog Devices: ADM485
- Maxim: MAX3485 / MAX487
(Note: pinouts and features vary; check for exact compatibility before substitution.)

Key features of the MAX485CPA+ (RS-485/RS-422 transceiver):
- 5V single-supply operation
- Half-duplex, 2-wire RS-485/RS-422 interface
- 1/8 unit-load on the bus (high node count)
- Data rates up to ~2.5 Mbps
- Independent DE (driver enable) and RE (receiver enable) with tri-state outputs
- Built-in fail-safe receiver: RO goes high if the bus is open, idle, or shorted
- Receiver common-mode input range: wide (-7V to +12V)
- Robust ESD protection on the bus pins
- Small 8-pin package options (DIP-8/SO-8) with low power standby
Optional notes: designed for low power consumption; suitable for multi-drop networks; no external biasing required for fail-safe in typical use.

MAX485CPA+ comes in an 8-pin package.
Pinout (pin 1 → pin 8):
- 1 RO: Receiver output (logic output of received data)
- 2 RĒ: Receiver enable (active low)
- 3 DE: Driver enable
- 4 DI: Driver input (data to transmit)
- 5 GND: Ground
- 6 B: RS-485 bus pin B (diff. line)
- 7 A: RS-485 bus pin A (diff. line; A is noninverting with respect to B)
- 8 VCC: Supply voltage (typ. 4.75–5.25 V)
Note: A/B are the differential bus lines; DE enables the driver, RĒ enables the receiver, and RO outputs the received data.

- Manufacturer: Maxim Integrated (the MAX485CPA+ was a Maxim product; Maxim is now part of Analog Devices, Inc.).
- Company type: American semiconductor company that designs analog and mixed-signal integrated circuits (largely fabless; manufacturing is outsourced).

MAX485CPA+ is a low‑power RS‑485/RS‑422 transceiver (half‑duplex). Typical application areas include:
- Industrial automation and control networks (PLCs, HMIs, motor drives) over multi‑drop RS‑485
- Building automation (HVAC, lighting, security, access control) and smart sensors
- Data acquisition and remote telemetry with long cable runs (meters to hundreds of meters)
- Instrumentation and test equipment needing robust noise immunity and failsafe biasing
- Industrial gateways and edge devices for distributed sensing/actuation in harsh environments

8-pin plastic DIP (PDIP) package.