Analog Devices Inc./Maxim Integrated MAX4535CUD+T

Overview

MAX4535CUD+T from Maxim Integrated is a dual 2-to-1 fault-protected analog multiplexer IC operating on ±4.5V to ±20V dual supplies or +9V to +36V single supply, featuring ±40V fault protection with supplies off, 400Ω max on-resistance, and rail-to-rail signal handling - used in avionics signal routing and industrial redundant systems where overvoltage resilience is critical.

For engineers reviewing the MAX4535CUD+T datasheet, MAX4535CUD+T pinout, MAX4535CUD+T application, or MAX4535CUD+T equivalent, this page delivers verified electrical specs, fault-protection behavior under ±25V/±40V conditions, dual-channel switching timing (20ns fault response), TTL/CMOS-compatible logic inputs, and real-world design implications for high-voltage data-acquisition interfaces.

Technical Context

The MAX4535CUD+T implements dual independent 2-to-1 multiplexers using parallel N- and P-channel FETs per channel to achieve low on-resistance and rail-to-rail conduction. Each NO_ input is fault-protected via internal comparators that detect >±150mV rail excursion and disable the channel FETs while clamping COM output to V+ or V− via booster FETs.

Fault response is asymmetric: positive faults clamp COM to V+ with ~2.5µs recovery; negative faults clamp to V− with ~1.3µs recovery. The COM pins are not fault-protected and must remain within V− to V+ - exceeding this risks ESD diode conduction and device damage.

Key Specifications

Pinout & Package

MAX4535CUD+T is housed in a 14-pin TSSOP package (JEDEC MO-153, 5.0mm × 4.4mm × 1.2mm body, 0.65mm pitch), optimized for high-density PCB layouts and thermal performance in industrial environments.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual 2-to-1 analog multiplexer applications.

Compared with ADG508FBRUZ and TMUX6219RTER, MAX4535CUD+T uniquely delivers dual independent 2-to-1 switching with guaranteed ±40V fault tolerance at zero supply voltage - making it irreplaceable in avionics and industrial safety-critical signal routing where power integrity cannot be assumed.

Availability

MAX4535CUD+T is available at Aetrix Electronics and suitable for avionics signal routing, industrial redundant systems, and data-acquisition front-ends requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX4535CUD+T 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) designs high-performance analog and mixed-signal ICs for demanding industrial, automotive, and communications applications.

The MAX4535 belongs to Maxim's fault-protected analog switch family, engineered specifically for high-voltage signal routing in safety-critical systems where overvoltage resilience, rail-to-rail operation, and power-off protection are mandatory.

FAQ

What is the maximum fault voltage the MAX4535CUD+T can withstand with power supplies disconnected?

The MAX4535CUD+T guarantees ±40V fault protection on NO_ pins when all supplies (V+ and V−) are disconnected. This allows safe connection to live field wiring during maintenance or hot-swap operations without risk of latch-up or permanent damage. The device enters high-impedance state on NO_ pins under fault, isolating downstream circuitry. This specification is validated per Absolute Maximum Ratings and confirmed in the Electrical Characteristics table under "NO_ Overvoltage with Switch Power Off".

Does the MAX4535CUD+T require power-supply sequencing during system startup?

No, the MAX4535CUD+T does not require power-supply sequencing. V+ and V− may be applied in any order or at different rates without causing malfunction or damage. This is enabled by internal bias networks and comparator architectures that remain functional across partial power states. The feature is explicitly listed under "Features" and verified in the Applications Information section - critical for ruggedized industrial and avionics platforms where rail ramp times vary significantly.

Can the COM pins of the MAX4535CUD+T be exposed to voltages outside the V+ to V− range?

No, the COM pins of the MAX4535CUD+T are not fault-protected and must remain strictly within the V− to V+ supply range at all times. Exceeding these limits forward-biases internal ESD diodes, risking excessive current flow (>30mA absolute max) and irreversible damage. This limitation is emphasized in the "Non-Fault-Protected Pins" subsection and Absolute Maximum Ratings - unlike NO_ pins, COM has no clamping or high-impedance fail-safe behavior.

What is the on-resistance matching between channels in the MAX4535CUD+T?

The MAX4535CUD+T guarantees ≤10Ω maximum on-resistance mismatch (∆RON) between its dual channels (e.g., NO1A/NO2A or NO1B/NO2B) under identical operating conditions. This tight matching ensures consistent gain and minimal offset error when routing differential or ratiometric sensor signals. The value is specified in the Electrical Characteristics table at TA = +25°C and confirmed across temperature in Typical Operating Characteristics plots (toc03/toc04).

How does the MAX4535CUD+T behave during a transient overvoltage event?

During a fast transient overvoltage on an NO_ pin, the MAX4535CUD+T responds in ≤20ns by disabling the channel FETs and clamping the COM output to V+ (for positive transients) or V− (for negative transients). Recovery after the transient returns within rails takes ~2.5µs (positive) or ~1.3µs (negative), depending on COM load capacitance and resistance. This behavior is detailed in the "Transient Fault Condition" section and validated in Figure 9 of the datasheet.