Analog Devices Inc./Maxim Integrated MAX367CWN+

Overview

MAX367CWN+ from Maxim Integrated is an 8-channel, two-terminal analog signal-line circuit protector IC designed for series insertion in sensitive analog interfaces. It operates with bipolar supplies (±2.25V to ±18V) or unipolar supplies (4.5V to 36V), delivers ≤100Ω on-resistance with power applied, maintains <1nA leakage at +25°C, and provides ±40V overvoltage protection - used in hot-insertion data-acquisition systems to prevent latch-up during power sequencing.

For engineers reviewing the MAX367CWN+ datasheet, MAX367CWN+ pinout, MAX367CWN+ application, or MAX367CWN+ equivalent, key selection criteria include fault knee voltage (≈1.3V below V+, ≈2.0V above V−), symmetrical IN/OUT interchangeability, open-circuit behavior with power off, and compatibility with high-impedance op-amp inputs requiring sub-nA leakage control.

Technical Context

The MAX367CWN+ integrates eight independent, symmetrical two-terminal protectors, each built from three enhancement-mode MOSFETs (two N-channel, one P-channel) that form a self-biasing, supply-driven clamping structure. Its operation requires no external controls or programming - protection activates automatically when input or output voltage approaches within ~1.5V of either supply rail.

During normal operation (signal within safe range), all FETs conduct to deliver low-impedance signal path (<100Ω typical); during fault conditions (e.g., ±35V transient with ±5V supplies), path resistance rises sharply to limit current while clamping output to ~1.3V below V+ or ~2.0V above V−. No fault current flows through V+ or V− pins - all fault current passes directly between IN and OUT terminals.

Key Specifications

Pinout & Package

MAX367CWN+ is housed in an 18-pin Wide SO (Small Outline) package, 0.300″ body width, with gull-wing leads and standard JEDEC MO-153 footprint. Pin 1 is located at the top-left corner (notch or dot indicator), and the package is RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog signal-line protection applications.

Compared with MAX367EPN+ and MAX366CSA+, the MAX367CWN+ delivers optimal balance of channel density, commercial-temperature reliability, and wide-SO manufacturability - making it the preferred choice for cost-sensitive, high-volume industrial data-acquisition modules requiring eight independent protected paths.

Availability

MAX367CWN+ is available at Aetrix Electronics and suitable for process control systems, hot-insertion ATE equipment, redundant backup monitoring, sensitive instrument front-ends, and data-acquisition systems requiring stable component supply across extended production lifecycles.

Supply support for MAX367CWN+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) is a fabless semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and computing applications.

The MAX366/MAX367 family was designed specifically to solve overvoltage-induced latch-up and damage in analog signal chains - targeting modular instrumentation, factory automation, and test equipment where signal integrity and fault resilience are non-negotiable.

FAQ

What is the maximum continuous fault voltage the MAX367CWN+ can withstand?

The MAX367CWN+ withstands up to ±40V differential between its IN and OUT terminals when V+ = V− = 0V. With powered supplies, maximum fault voltage is supply-dependent - e.g., ±35V with ±5V supplies or ±25V with ±15V supplies. This rating is specified in Absolute Maximum Ratings and confirmed by transfer characteristic curves in the datasheet.

Can the MAX367CWN+ be used with single-supply op-amps operating from +5V and ground?

Yes - configure V− = 0V (ground) and V+ = +5V. The MAX367CWN+ supports unipolar operation from +4.5V to +36V. Note that signals near 0V (below ~2V) enter fault condition; for true ground-referenced signals, ensure downstream circuitry tolerates the ~1.3V clamp offset or add external pull-downs.

Does the MAX367CWN+ require external biasing or control signals to function?

No - the MAX367CWN+ is fully autonomous. It draws <1µA supply current and requires only V+ and V− connections. All eight protectors activate automatically based on internal FET thresholds; no enable pins, logic inputs, or programming interfaces exist on the MAX367CWN+.

How does the MAX367CWN+ behave during power-up and power-down transitions?

During ramp-up, the MAX367CWN+ remains in high-impedance fault state until V+ and V− exceed the input voltage by ~1.5V; output follows input only after supply stabilization. During ramp-down, it reverts to open-circuit behavior before supply collapse - preventing backfeed and ensuring clean signal isolation throughout sequencing.

Is the MAX367CWN+ pin-compatible with other members of the MAX366/MAX367 family?

Yes - MAX367CWN+ shares identical pinout with all 18-pin MAX367 variants (e.g., MAX367CPN+, MAX367EWN+). However, it is not pin-compatible with the 8-pin MAX366 series. Always verify temperature grade and package suffix (C = 0°C to +70°C, W = Wide SO) when substituting.