Analog Devices Inc./Maxim Integrated MAX4535ESD

Overview

MAX4535ESD 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. It features ±40V overvoltage protection with supplies off, 400Ω max on-resistance, rail-to-rail signal handling, and 20ns typical fault response time. It is used in avionics signal routing where high-voltage fault tolerance and channel redundancy are critical.

For engineers reviewing the MAX4535ESD datasheet, MAX4535ESD pinout, MAX4535ESD application, or MAX4535ESD equivalent, key selection criteria include fault protection level (±40V power-off), dual-channel 2:1 switching architecture, TSSOP-14 package compatibility, and TTL/CMOS logic interface at ±15V or +12V supply.

Technical Context

The MAX4535ESD implements dual independent 2-to-1 multiplexers using parallel N- and P-channel FETs per switch path, enabling low on-resistance and true rail-to-rail analog signal pass-through. Each NO_ input is fault-protected with internal comparators that clamp COM outputs to V+ or V− within ~150mV of rail violation.

Fault detection triggers immediate high-impedance isolation of the affected NO_ pin regardless of enable or address state; during active faults, "booster" FETs source/sink up to ±10mA to maintain COM clamping. Non-fault-protected pins (COMA, COMB, A0, EN, GND) require voltage limiting to supply rails to avoid ESD diode conduction.

Key Specifications

Pinout & Package

MAX4535ESD is housed in a 14-pin TSSOP package (JEDEC MO-153, 5.0mm × 4.4mm × 1.2mm), rated for −40°C to +85°C operation. Pin 1 is A0; pin 2 is EN; pins 3 and 12 are V− and V+; pins 4, 5, 10, and 11 are fault-protected NO inputs (NO1A, NO2A, NO1B, NO2B); pins 7 and 8 are COM outputs (COMA, COMB); pin 13 is GND; pins 6, 9, and 14 are no-connect.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADG5234BRUZ and TMUX6234RTER, MAX4535ESD uniquely delivers dual independent 2:1 switching with ±40V power-off fault tolerance in a compact TSSOP-14, making it optimal for space-constrained avionics and redundant I/O where supply robustness and channel independence are non-negotiable.

Availability

MAX4535ESD is available at Aetrix Electronics and suitable for avionics signal routing, industrial redundant I/O, and data-acquisition front-end designs requiring stable component supply across extended temperature and high-reliability qualification cycles.

Supply support for MAX4535ESD 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 semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX4535 belongs to Maxim's fault-protected analog switch family, engineered for mission-critical systems where signal integrity must be preserved despite wiring faults, sensor disconnection, or power anomalies.

FAQ

What is the maximum fault voltage the MAX4535ESD can withstand with power supplies disconnected?

The MAX4535ESD sustains ±40V on its NO_ pins (NO1A, NO2A, NO1B, NO2B) when V+ and V− are at 0V. This is specified in the Absolute Maximum Ratings table and verified under power-off conditions. The device enters high-impedance isolation mode, preventing current flow into the COM outputs. This capability makes MAX4535ESD suitable for maintenance scenarios where field wiring may be exposed to accidental contact with higher-voltage sources while the system is de-energized.

Does the MAX4535ESD require power-supply sequencing during startup?

No, the MAX4535ESD does not require power-supply sequencing. Its internal architecture allows safe operation regardless of the order in which V+ and V− are applied. This eliminates the need for external sequencing circuits in complex multi-rail systems. The MAX4535ESD remains functional and fault-protected even if V+ ramps before V− or vice versa - a key advantage confirmed in the Features section and validated across temperature extremes in the Electrical Characteristics tables.

Can the COMA and COMB pins of the MAX4535ESD be overvolted beyond the supply rails?

No, the COMA and COMB pins of the MAX4535ESD are not fault-protected and must remain within the V− to V+ supply range at all times. Exceeding these limits forward-biases internal ESD diodes, risking permanent damage. The datasheet explicitly states this limitation in the "Non-Fault-Protected Pins" section and Absolute Maximum Ratings. Users must ensure external clamping or voltage limiting is applied to COM outputs if connected to uncontrolled loads - a design constraint directly tied to the MAX4535ESD's internal FET topology.

What is the typical on-resistance matching between channels in the MAX4535ESD?

The MAX4535ESD guarantees ≤10Ω maximum on-resistance mismatch (∆RON) between any two channels under identical operating conditions. This value is measured as RON(MAX) − RON(MIN) and is tested across temperature and supply voltage ranges. Tight matching ensures consistent gain and phase response in differential or ratiometric measurement systems - a specification explicitly documented in the Electrical Characteristics tables for both dual-supply and single-supply configurations of the MAX4535ESD.

Is the MAX4535ESD compatible with TTL and CMOS logic levels?

Yes, the MAX4535ESD accepts TTL- and CMOS-compatible logic inputs: VA_L ≤ 0.8V (low) and VA_H ≥ 2.4V (high), valid across its full supply range (±4.5V to ±20V or +9V to +36V). This is confirmed in the Logic Input section of the Electrical Characteristics table and enables direct interfacing with standard microcontrollers, FPGAs, and logic families without level-shifting circuitry - a feature explicitly highlighted in the General Description and Applications sections of the MAX4535ESD datasheet.