Analog Devices Inc./Maxim Integrated DG309CJ+

Overview

DG309CJ+ from Maxim Integrated is a quad SPST analog switch with normally closed (NC) configuration, designed for precision signal routing in mixed-signal systems. It delivers 60Ω typical on-resistance, <120ns turn-on time, and supports ±5V to ±20V dual supplies or +5V to +30V single supply, enabling use in military radios and guidance systems where rail-to-rail analog switching is required.

For engineers reviewing the DG309CJ+ datasheet, DG309CJ+ pinout, DG309CJ+ application, or DG309CJ+ equivalent, key selection criteria include its NC logic behavior, 44V breakdown rating, CMOS-compatible inputs, and guaranteed operation across 0°C to +70°C in 16-pin plastic DIP packaging.

Technical Context

The DG309CJ+ implements monolithic low-power CMOS architecture with substrate-connected V+ pin, enabling robust analog signal blocking up to ±30V peak-to-peak when off. Its four independent channels each feature matched rDS(ON) and leakage performance across temperature.

Switching is controlled by TTL/CMOS-compatible digital inputs (IN1–IN4), with logic high disabling conduction (NC state). The device maintains analog signal integrity via low charge injection (±10pC) and minimal channel capacitance (CD(ON)+CS(ON) = 27pF).

Key Specifications

Pinout & Package

Package: 16-pin plastic DIP (0.300" wide), through-hole mountable with standard 0.1" grid spacing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADG409BNZ and TS5A23157PWR, the DG309CJ+ uniquely bridges high-voltage bipolar operation and single-supply convenience in through-hole packaging - making it irreplaceable in legacy military and test equipment upgrades requiring drop-in mechanical fit and extended voltage range.

Availability

DG309CJ+ is available at Aetrix Electronics and suitable for military radios, guidance and control systems, and test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DG309CJ+ 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 demanding industrial, automotive, and communications applications.

The DG309CJ+ belongs to Maxim's legacy analog switch family engineered specifically for high-reliability signal routing in defense, aerospace, and automated test equipment where voltage range, leakage, and timing predictability are non-negotiable.

FAQ

What is the logic behavior of DG309CJ+ compared to DG308ACJ+?

The DG309CJ+ is normally closed (NC): each channel conducts when its INx input is logic low (≤0.8V), and opens when high (≥2.4V). In contrast, DG308ACJ+ is normally open (NO), conducting only when INx is high. This complementary pairing allows designers to implement fail-safe or default-path signal routing using identical pinouts and supply configurations - both share identical rDS(ON), timing, and voltage ratings.

Can DG309CJ+ operate from a single +12V supply?

Yes, DG309CJ+ supports single-supply operation from +5V to +30V. When using +12V, connect V− to GND and route analog signals between 0V and +12V. Note that rDS(ON) increases slightly versus ±15V operation, and turn-on time degrades to ~200ns - verified in the "Applications Information" section of the DG309CJ+ datasheet under single-supply conditions.

What is the purpose of the N.C. pin (Pin 12) on DG309CJ+?

Pin 12 on DG309CJ+ is a true no-connect terminal - not internally bonded to any die structure. It must remain unconnected in PCB layout to prevent parasitic coupling or mechanical stress-induced failure. Maxim explicitly states this in the "Pin Description" table; connecting Pin 12 risks compromising isolation performance or causing unexpected leakage paths in high-precision applications.

How does DG309CJ+ handle analog signals exceeding the supply rails?

DG309CJ+ does not tolerate analog signals beyond its supply rails: absolute maximum ratings restrict VANALOG to V− ≤ VS/VD ≤ V+. Exceeding this causes forward-biasing of internal ESD diodes, leading to increased leakage or permanent damage. For overvoltage protection, external clamping diodes referenced to V+ and V− are required - confirmed by the "Absolute Maximum Ratings" table limiting analog input to ±15V under ±15V supplies.

Is DG309CJ+ suitable for audio signal switching?

Yes, DG309CJ+ is widely used in professional audio routing due to its 60Ω rDS(ON), low 10pC charge injection, and 27pF channel capacitance - parameters that minimize THD+N and crosstalk in line-level (±10V) paths. Its 0°C to +70°C temperature range and DIP package support serviceable rack-mounted gear, and the NC configuration provides fail-closed mute paths essential in broadcast safety systems.