Analog Devices Inc./Maxim Integrated MAX4535CSD

Overview

MAX4535CSD from Maxim Integrated is a dual 2-to-1 fault-protected analog multiplexer with ±4.5V to ±20V dual-supply or +9V to +36V single-supply operation, 400Ω max on-resistance, ±40V fault protection with supplies off, and rail-to-rail signal handling - used in avionics signal routing and industrial redundant systems where overvoltage resilience is critical.

For engineers reviewing the MAX4535CSD datasheet, MAX4535CSD pinout, MAX4535CSD application, or MAX4535CSD equivalent, this page delivers verified electrical specs, fault-protection behavior under supply-on/off conditions, TTL/CMOS-compatible logic thresholds, and real-world design implications for high-voltage analog switching in safety-critical environments.

Technical Context

The MAX4535CSD 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 signal conduction. Each NO_ input features dedicated comparators that detect >±150mV excursions beyond V+/V− rails, triggering immediate high-impedance isolation of the NO_ pin.

During overvoltage faults with supplies active, COM outputs are clamped to V+ or V− via internal "booster" FETs capable of ±10mA sourcing/sinking; with supplies off, NO_ pins become virtual open circuits up to ±40V. COM_ pins lack fault protection and must remain within supply rails.

Key Specifications

Pinout & Package

MAX4535CSD is housed in a 14-pin TSSOP package (JEDEC MO-153, 4.4mm × 5.0mm), optimized for high-density PCB layouts and thermal performance in industrial control modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fault-protected analog multiplexer applications.

Compared with ADG508FBRUZ and TS5A3157DCKR, the MAX4535CSD uniquely delivers dual independent fault-protected 2-to-1 switching in a single TSSOP package with bipolar/high-voltage supply flexibility - essential for avionics and industrial control where channel isolation and overvoltage resilience are non-negotiable.

Availability

MAX4535CSD is available at Aetrix Electronics and suitable for avionics signal routing, industrial redundant sensors, and data-acquisition front-ends requiring stable component supply across extended temperature and voltage ranges.

Supply support for MAX4535CSD 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 precision analog, mixed-signal, and power-management ICs for demanding industrial, automotive, and communications applications.

The MAX4535CSD belongs to Maxim's fault-protected analog switch family, engineered specifically for high-reliability signal routing in environments subject to wiring faults, ESD, and lightning-induced transients.

FAQ

What is the maximum allowable voltage on NO pins of the MAX4535CSD when supplies are powered off?

The MAX4535CSD guarantees ±40V fault protection on NO_ pins (NO1A, NO1B, NO2A, NO2B) with supplies off. This means the device remains undamaged and maintains high-impedance isolation even when subjected to ±40V DC or transient voltages relative to GND, making it ideal for maintenance scenarios where field wiring remains energized while system power is removed. The MAX4535CSD datasheet confirms this rating under Absolute Maximum Ratings and Fault Protection sections.

Can the MAX4535CSD operate with asymmetric dual supplies, such as +12V and −5V?

Yes, the MAX4535CSD supports asymmetric dual supplies - the specification requires only that V+ and V− fall within ±4.5V to ±20V individually and that their absolute sum does not exceed 44V. A +12V/−5V configuration satisfies both conditions (|+12| + |−5| = 17V < 44V), and the device maintains full rail-to-rail signal handling from −5V to +12V. This capability is explicitly validated in the Electrical Characteristics tables for dual-supply operation.

Why are COMA and COMB pins not fault-protected on the MAX4535CSD?

The MAX4535CSD design intentionally omits fault protection on COMA and COMB pins because they serve as output nodes - clamping them would compromise signal fidelity and introduce distortion. Instead, the datasheet mandates that COM pins remain strictly within V− to V+ to prevent forward-biasing internal ESD diodes. This architectural choice prioritizes analog performance and enables precise output clamping *only* during NO_-side faults, as confirmed in the Detailed Description and Absolute Maximum Ratings sections.

Does the MAX4535CSD require external pull-up or pull-down resistors on A0, A1, or EN pins?

No, the MAX4535CSD does not require external biasing on A0, A1, or EN - its TTL/CMOS-compatible logic inputs have defined thresholds (V_IL ≤ 0.8V, V_IH ≥ 2.4V) and internal input structures that ensure reliable switching with standard microcontroller or FPGA GPIO outputs. The datasheet specifies logic current <±1µA, confirming negligible loading; adding external resistors would unnecessarily increase board area and risk threshold violation under noise or leakage conditions.

How does the MAX4535CSD behave during a transient overvoltage event exceeding ±25V with supplies on?

During a transient overvoltage on any NO_ pin exceeding ±25V with supplies on, the MAX4535CSD responds in two phases: first, within 20ns, the affected NO_ pin goes high-impedance; second, if the corresponding channel is ON, COMA or COMB is actively clamped to V+ or V− via internal booster FETs. Recovery occurs in ~1.3µs (negative fault) or ~2.5µs (positive fault), as measured in the Transient Fault Condition section - behavior fully characterized in Figures 9 and the Electrical Characteristics table.