Analog Devices Inc./Maxim Integrated MAX328ETE+T

Overview

The MAX328ETE+T from Maxim Integrated is a monolithic CMOS 1-of-8 single-ended analog multiplexer designed for high-precision signal routing in data-acquisition and fault-tolerant systems. It features ultra-low off-leakage (≤1 pA at +25°C), 2.5 kΩ typical on-resistance, ±5V to ±18V dual-supply operation, bidirectional signal handling, and operates across -40°C to +85°C. It serves as a pin-for-pin replacement for DG508 in high-impedance sensor front-ends interfacing with precision op amps or ADCs.

For engineers reviewing the MAX328ETE+T datasheet, MAX328ETE+T pinout, MAX328ETE+T application, or MAX328ETE+T equivalent, key selection criteria include leakage-critical switching, rail-to-rail analog signal range, fault-tolerant design capability with external 40kΩ resistors, TTL/CMOS logic compatibility, and TQFN-EP package thermal performance for space-constrained industrial instrumentation.

Technical Context

The MAX328ETE+T implements a CMOS transmission-gate architecture with latchup-proof construction, enabling robust operation under unbalanced supply conditions (e.g., +12V/–5V). Its address decoding logic (A0–A2) selects one of eight bidirectional analog inputs (S1–S8) to the common drain D, controlled by an active-high EN pin.

It supports both single-supply (10V–30V) and dual-supply (±5V–±18V) configurations, with analog signal range extending to the supply rails. The device guarantees ≤1.5 µs switching time and ≤0.2 µs break-before-make interval, ensuring minimal signal disruption during channel transitions.

Key Specifications

Pinout & Package

MAX328ETE+T uses a 16-pin TQFN-EP (4mm × 4mm, 0.5mm pitch) with exposed pad connected to V+. This package provides low thermal resistance and compact footprint for dense PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX358ETE+, MAX328ETE+T delivers extended temperature range without trade-offs in leakage or on-resistance; versus ADG508ATQNZ, it sacrifices on-resistance for 100× lower leakage-making it irreplaceable in electrometer and precision DAQ front-ends.

Availability

MAX328ETE+T is available at Aetrix Electronics and suitable for high-voltage data acquisition, fault-tolerant sensor multiplexing, and precision instrumentation front-ends requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX328ETE+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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and consumer applications.

The MAX328ETE+T belongs to Maxim's ultra-low-leakage analog switch/multiplexer product line, engineered specifically for precision measurement systems where signal integrity, fault resilience, and temperature stability are non-negotiable design requirements.

FAQ

What is the maximum continuous analog signal voltage range supported by the MAX328ETE+T?

The MAX328ETE+T supports an analog signal range from V− to V+, which spans ±15V when operated with ±15V supplies. With ±18V supplies, the range extends to ±18V. Absolute maximum ratings allow V+ up to +44V referenced to V−, but functional analog range remains bounded by the supply rails. This rail-to-rail capability eliminates level-shifting needs in ±15V industrial control systems using the MAX328ETE+T.

Does the MAX328ETE+T require external protection components to survive 120V AC faults?

No, the MAX328ETE+T does not require external clamping diodes for 120V AC fault protection when used with 40kΩ series resistors at each input. Its internal ESD structure and guaranteed <1 pA leakage enable indefinite fault survival while limiting error to <40 nV. This integrated fault tolerance is a core design feature of the MAX328ETE+T, distinguishing it from conventional multiplexers that mandate discrete protection.

Is the MAX328ETE+T pin-compatible with the DG508, and what does that mean for PCB layout?

Yes, the MAX328ETE+T is pin-for-pin compatible with the DG508 in its TQFN-EP package variant. This means the MAX328ETE+T occupies identical board space, uses the same pad layout, and connects to identical traces-enabling direct replacement without PCB rework. All signal, supply, and control pins (A0–A2, EN, S1–S8, D, V+, V−, GND) map identically, preserving existing routing and grounding schemes in legacy DG508-based designs.

How does the MAX328ETE+T perform with unbalanced supply voltages like +12V and –5V?

The MAX328ETE+T is explicitly characterized for unbalanced supply operation, including combinations such as +12V/–5V or +5V/–15V. Its CMOS switch architecture maintains specified on-resistance, leakage, and switching speed across these conditions. This flexibility allows the MAX328ETE+T to interface seamlessly with mixed-rail systems-e.g., +12V analog sections and –5V reference stages-without performance degradation or additional biasing circuitry.

What is the thermal performance advantage of the TQFN-EP package used in the MAX328ETE+T?

The TQFN-EP package of the MAX328ETE+T features an exposed thermal pad (EP) that must be soldered to a V+-connected PCB copper pour. This configuration achieves a junction-to-ambient thermal resistance (θ_JA) of 2.67°C/W-significantly lower than SO or DIP alternatives. As a result, the MAX328ETE+T sustains full-spec operation at higher ambient temperatures and enables compact, high-density layouts in thermally constrained applications like portable DAQ modules.