Analog Devices Inc./Maxim Integrated MAX306EQI+

Overview

MAX306EQI+ from Maxim Integrated is a precision 1-of-16 single-ended CMOS analog multiplexer designed for high-fidelity signal routing in demanding measurement and control systems. It delivers <100Ω on-resistance, <5Ω channel-to-channel matching, <10pC charge injection, rail-to-rail analog signal handling (±15V dual or 0–12V single supply), and operates across –40°C to +85°C in a 28-pin PLCC package.

For engineers reviewing the MAX306EQI+ datasheet, MAX306EQI+ pinout, MAX306EQI+ application, or MAX306EQI+ equivalent, key selection criteria include guaranteed on-resistance flatness (≤7Ω), ultra-low leakage (<2.5nA NO off-leakage at +85°C), fast switching (<250ns transition time), ESD protection (>2000V), and plug-in compatibility with industry-standard DG406/DG506A devices.

Technical Context

The MAX306EQI+ implements a monolithic CMOS decoder-multiplexer architecture with four address inputs (A0–A3), an active-high enable (EN), and a single bidirectional COM output. Its silicon-gate process ensures matched switch characteristics and minimal signal distortion across the full analog range.

It supports flexible power configurations: bipolar ±4.5V to ±20V or single +5V to +30V (with V− tied to GND). Logic inputs are TTL/CMOS-compatible, and internal clamping diodes protect against overvoltage on NO, COM, and address pins - critical for rugged test equipment and military radio interfaces.

Key Specifications

Pinout & Package

MAX306EQI+ is housed in a 28-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead configuration, qualified for –40°C to +85°C operation and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX306EUI+, MAX306EQI+ offers superior mechanical stability and thermal mass in PLCC packaging, while DG406DN+ trades measurable performance (RON, matching, ESD) for broader legacy availability - making MAX306EQI+ the optimal choice for new designs demanding guaranteed precision and ruggedness.

Availability

MAX306EQI+ is available at Aetrix Electronics and suitable for sample-and-hold circuits, test equipment, military radios, battery-operated systems, and guidance and control systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX306EQI+ 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 leader in precision analog, mixed-signal, and high-reliability semiconductor solutions, serving industrial, automotive, communications, and defense markets since 1983.

The MAX306/MAX307 family was engineered for high-performance analog signal routing in mission-critical systems - emphasizing low distortion, guaranteed matching, and wide supply flexibility to replace aging industry-standard muxes with measurable improvements.

FAQ

What is the maximum analog signal voltage range supported by the MAX306EQI+?

The MAX306EQI+ supports an analog signal range of ±15V when operated from bipolar ±15V supplies, and 0V to +12V when operated from a +12V single supply (with V− tied to GND). Absolute maximum ratings allow V+ up to +44V and V− down to –44V relative to GND, but signal swing remains constrained by supply rails. These ranges are fully specified and tested across the –40°C to +85°C temperature range for the MAX306EQI+.

Does the MAX306EQI+ require external pull-up resistors on its address or enable pins?

No, the MAX306EQI+ does not require external pull-up resistors on A0–A3 or EN. Its CMOS inputs exhibit low leakage (<±1.0µA) and are compatible with standard TTL/CMOS logic levels (VAL ≤ 0.8V, VAH ≥ 2.4V). Internal design ensures proper logic recognition without external biasing - simplifying interface design and reducing BOM count in microcontroller-driven systems using the MAX306EQI+.

Can the MAX306EQI+ be used with unbalanced supply voltages such as +24V and –5V?

Yes, the MAX306EQI+ supports unbalanced supplies - for example, +24V on V+ and –5V on V− - as long as the difference between V+ and V− does not exceed +44V and each supply remains within its absolute maximum rating (V+ ≤ +44V, V− ≥ –44V). This capability enables flexible power architecture in mixed-signal systems, and all key specifications (on-resistance, leakage, switching speed) remain valid for the MAX306EQI+ under such conditions.

How does the MAX306EQI+ achieve its guaranteed on-resistance matching of <5Ω?

The MAX306EQI+ achieves <5Ω on-resistance matching through Maxim's proprietary 44V silicon-gate CMOS process and laser-trimmed layout symmetry across all 16 switch channels. Matching is measured at TA = +25°C with INO = –1.0mA and VCOM = ±10V, and guaranteed over temperature via process controls - not post-package trimming. This specification is explicitly validated for the MAX306EQI+ and forms the basis for its use in precision gain-setting and calibration applications.

Is the MAX306EQI+ pin-compatible with the DG406 or DG506A?

Yes, the MAX306EQI+ is a pin-compatible, functionally identical plug-in upgrade for the DG406 and DG506A in the 28-pin PLCC package. Pin assignments for V+, V−, GND, COM, NO1–NO16, A0–A3, EN, and N.C. terminals match exactly. No PCB redesign is required - users gain immediate improvements in on-resistance, matching, charge injection, and ESD protection while retaining full backward compatibility with existing DG406/DG506A layouts and firmware.