Analog Devices Inc./Maxim Integrated MAX309CSE

Overview

The MAX309CSE from Maxim Integrated is a precision differential 2-of-4 CMOS analog multiplexer designed for bidirectional signal routing in high-fidelity analog systems. It features <100Ω on-resistance, <5Ω channel-to-channel matching, <10pC charge injection, <5nA NO-off leakage at +85°C, and rail-to-rail signal handling up to ±20V bipolar or +30V single supply - enabling accurate signal selection in sample-and-hold circuits and military-grade communications systems.

For engineers reviewing the MAX309CSE datasheet, MAX309CSE pinout, MAX309CSE application, or MAX309CSE equivalent, this device is evaluated for low-distortion analog switching in battery-operated test equipment, guidance systems, and audio routing where leakage, flatness, and charge injection directly impact measurement integrity and dynamic range.

Technical Context

The MAX309CSE implements a CMOS decode logic architecture with dual 4-channel differential switching paths (COMA/NO1A–NO4A and COMB/NO1B–NO4B), controlled by A0/A1 address inputs and an active-low EN enable. Its silicon-gate process ensures guaranteed on-resistance flatness of ≤7Ω over ±10V signal range and matched channel R_ON variation ≤5Ω.

It supports TTL/CMOS-compatible logic inputs (VAL ≤ 0.8V, VAH ≥ 2.4V) and operates across ±5V to ±20V bipolar or +5V to +30V single supplies, with internal ESD protection >2000V and no external clamping diodes required under normal bias conditions.

Key Specifications

Pinout & Package

MAX309CSE is housed in a 16-pin narrow SO (Small Outline) package, 3.9mm wide, with standard JEDEC MS-012AC footprint and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX309CSE, MAX309ESE offers identical performance with extended temperature qualification, while ADG409BRUZ trades guaranteed matching and low charge injection for broader supply voltage and lower unit cost - making MAX309CSE optimal for precision, temperature-stable analog routing where channel consistency is mandatory.

Availability

MAX309CSE is available at Aetrix Electronics and suitable for automatic test equipment, military radio subsystems, sample-and-hold circuits, and audio signal routing requiring stable component supply across commercial temperature range (0°C to +70°C).

Supply support for MAX309CSE 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 computing markets.

The MAX308/MAX309 product line was engineered for precision analog signal routing in mission-critical systems - emphasizing low leakage, matched on-resistance, and robust ESD tolerance in harsh electrical environments.

FAQ

What is the maximum analog signal range supported by the MAX309CSE?

The MAX309CSE supports an analog signal range of ±10V when operated with ±15V supplies, and scales linearly with supply voltage - e.g., ±5V with ±10V supplies or 0V to +12V with +12V single supply. This rail-to-rail capability ensures full dynamic range utilization in instrumentation and audio applications without signal clipping. The MAX309CSE maintains specified on-resistance flatness only within the voltage range explicitly tested and guaranteed in the datasheet.

Is the MAX309CSE pin-compatible with the DG409 analog multiplexer?

Yes, the MAX309CSE is a direct plug-in upgrade for the DG409, sharing identical pinout, logic interface, and functional behavior. It improves upon the DG409 with lower on-resistance (<100Ω vs. ~120Ω), tighter matching (<5Ω vs. unspecified), reduced charge injection (<10pC vs. ~25pC), and enhanced ESD protection (>2000V vs. ~200V). No PCB changes are required when replacing DG409 with MAX309CSE in existing designs.

Does the MAX309CSE require external clamping diodes for overvoltage protection?

No, the MAX309CSE does not require external clamping diodes under normal operating conditions. Its internal ESD protection structure provides >2000V HBM rating and inherent diode clamping on NO, COM, EN, and address pins. External diodes are recommended only if absolute maximum ratings (e.g., V+ to V− >44V or input transients exceeding (V− −2V) to (V+ +2V)) may be violated - in which case they reduce usable analog range by ~1V but preserve MAX309CSE's core switching performance.

What is the guaranteed on-resistance matching specification for the MAX309CSE?

The MAX309CSE guarantees on-resistance matching of <5Ω maximum between any two channels across the full operating temperature range (0°C to +70°C). This parameter - defined as ∆R_ON = R_ON(MAX) − R_ON(MIN) - is 100% tested and ensures minimal gain mismatch in differential signal paths, such as those used in precision instrumentation amplifiers or balanced communication interfaces where common-mode rejection depends on switch symmetry.

Can the MAX309CSE operate from a single +5V supply?

Yes, the MAX309CSE supports single-supply operation from +5V to +30V. When using +5V, V− must be connected to GND, and the analog signal range reduces to 0V to +5V. Note that switching speed degrades significantly at +5V - transition time increases to ~600ns (vs. <250ns at ±15V) - so +5V operation is best suited for low-frequency signal routing where speed is secondary to low power consumption (<300µW typical).