Analog Devices Inc./Maxim Integrated DG509ADY

Overview

DG509ADY from Maxim Integrated is a differential 4-channel (2-of-8) monolithic CMOS analog multiplexer with break-before-make switching, ±4.5V to ±18V dual-supply operation, and 16-pin narrow SOIC package rated for -40°C to +85°C. It routes differential analog signals in data-acquisition systems with <1μs switching time, <0.7μs enable turn-off, and <500Ω typical on-resistance at ±15V.

For engineers reviewing the DG509ADY datasheet, DG509ADY pinout, DG509ADY application, or DG509ADY equivalent, key selection criteria include its differential channel architecture, guaranteed latchup immunity during signal-present power-down, symmetrical bidirectional analog path, and TTL/CMOS-compatible logic inputs with sub-10μA leakage.

Technical Context

The DG509ADY implements a CMOS decode logic block that selects one of four differential pairs (S1A/S1B through S4A/S4B) using two address bits (A0, A1) and an active-high enable (EN). Its internal switch structure ensures strict break-before-make timing (≤0.2μs) to prevent signal shorting during channel transitions.

All analog terminals (S1A–S4A, S1B–S4B, DA, DB) support bidirectional signal flow across the full ±15V analog range, with off-isolation of 68dB at 500kHz and drain/source off-capacitance of 12pF/5pF respectively - critical for high-fidelity signal routing in precision measurement front-ends.

Key Specifications

Pinout & Package

Package: 16-pin narrow SOIC (S16-5), RoHS-compliant, -40°C to +85°C operating range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DG509ADY, MAX339CPE+ delivers superior on-resistance and power efficiency at lower voltages, while ADG509ATQ offers space savings via TSSOP packaging - neither provides the same ±15V analog range or guaranteed latchup immunity under signal-present power-down conditions as DG509ADY.

Availability

DG509ADY is available at Aetrix Electronics and suitable for data-acquisition systems, aircraft heads-up displays, and control systems requiring stable component supply with guaranteed -40°C to +85°C performance and long-term industrial availability.

Supply support for DG509ADY 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 industrial, automotive, and communications applications.

The DG509ADY belongs to Maxim's legacy monolithic CMOS analog multiplexer product line, engineered specifically for high-reliability signal routing in ±15V instrumentation and aerospace systems where latchup immunity and break-before-make integrity are mandatory.

FAQ

What is the minimum dual-supply voltage required for reliable operation of the DG509ADY?

The DG509ADY requires a minimum dual-supply voltage of ±9V for continuous operation, as explicitly specified in the datasheet for DG509ADY/MY variants. Operation below ±9V may result in degraded on-resistance, increased leakage, or failure to meet break-before-make timing specifications. The device supports up to ±18V, making it compatible with standard ±15V industrial rails.

Does the DG509ADY support bidirectional analog signal flow on all channels?

Yes, the DG509ADY supports fully symmetrical bidirectional operation on all analog terminals - including S1A–S4A, S1B–S4B, DA, and DB. This allows the same physical channel to serve as either input or output depending on system configuration, with matched on-resistance and capacitance characteristics in both directions - essential for flexible test equipment and reconfigurable signal paths.

How does the DG509ADY prevent latchup when power supplies are turned off while analog signals remain present?

The DG509ADY uses latchup-proof CMOS construction with integrated protection structures that prevent parasitic SCR triggering. When V+ and V− are removed while analog signals persist on S or D pins, internal clamping diodes limit terminal voltage excursions, and the design ensures no DC path forms between supplies - allowing safe hot-swap or partial-power-down scenarios without damage or undefined behavior in the DG509ADY.

What is the purpose of the break-before-make timing specification in the DG509ADY?

The break-before-make timing (≤0.2μs) in the DG509ADY ensures that one differential channel is fully disconnected before the next is connected. This eliminates momentary short-circuits between differential pairs during switching - critical for maintaining signal integrity in precision measurement systems where even nanosecond-level shorts can induce transients, offset errors, or damage sensitive downstream circuitry in the DG509ADY signal path.

Can the DG509ADY be used with single-supply systems?

No, the DG509ADY is designed exclusively for dual-supply operation (±V). It lacks internal level-shifting or rail-to-rail input capability required for true single-supply use. Attempting to operate it with only V+ and GND (or V− and GND) will violate absolute maximum ratings and cause functional failure. For single-supply applications, consider the MAX338/MAX339 family, which Maxim explicitly recommends as alternatives for 5V-only designs.