Analog Devices Inc./Maxim Integrated DG425CY

Overview

DG425CY from Maxim Integrated is a dual, single-pole/single-throw (SPST) CMOS analog switch with latched TTL/CMOS-compatible control inputs, 20Ω typical on-resistance, ±4.5V to ±20V bipolar or +10V to +30V single-supply operation, and rail-to-rail signal handling - used in battery-powered test equipment and audio routing where low charge injection (15pC max) and tight on-resistance matching (3Ω max) are critical.

For engineers reviewing the DG425CY datasheet, DG425CY pinout, DG425CY application, or DG425CY equivalent, key selection criteria include latch timing (tWW = 200ns), off-leakage current (<5nA at +85°C), ESD tolerance (2000V min), and compatibility with microprocessor-controlled signal path switching in space-constrained industrial and communications systems.

Technical Context

The DG425CY implements two independent SPST switches with separate S1/D1 and S2/D2 signal paths, each controlled by a dedicated input (IN1/IN2) and managed via WR (write) and RS (reset) latching logic. Its silicon-gate CMOS process enables rail-to-rail analog conduction and guarantees on-resistance flatness of 4Ω max over the full signal range under bipolar supply conditions.

Latch operation allows transparent data entry when WR = 1 and RS = X, stores control states when WR = 0 and RS = X, and resets all switches to OFF state when RS = 0. Input thresholds are fixed at VINH ≥ 2.4V and VINL ≤ 0.8V, ensuring robust interfacing with standard logic families without level-shifting.

Key Specifications

Pinout & Package

Package: 16-pin SO (Small Outline) - surface-mount, 3.9mm × 9.9mm body, 1.27mm pitch, JEDEC MS-012AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DG425CY, ADG425BRZ trades latch capability and tighter leakage/matching for broader single-supply flexibility, while TS5A23157DCUR delivers ultra-low on-resistance at the expense of bipolar operation and thermal stability - making DG425CY the only choice for latched, high-accuracy, wide-supply analog routing in industrial and defense systems.

Availability

DG425CY is available at Aetrix Electronics and suitable for battery-operated systems, test equipment multiplexing, and audio signal routing requiring stable component supply across commercial temperature ranges (0°C to +70°C) and long-term production continuity.

Supply support for DG425CY 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, medical, communications, and automotive applications - emphasizing reliability, low power, and high integration.

The DG425CY belongs to Maxim's legacy DG42x family of latched CMOS analog switches, engineered specifically for microprocessor-controlled signal routing in environments demanding low leakage, rail-to-rail performance, and robust ESD immunity.

FAQ

What is the maximum analog signal voltage range supported by the DG425CY?

The DG425CY supports analog signals from V− to V+, enabling rail-to-rail operation. With ±15V supplies, it handles ±15V signals; with +12V/0V single supply, it handles 0V to +12V. Absolute maximum ratings allow V+ up to +44V relative to V−, but signal range remains bounded by the applied supply rails. This behavior is confirmed in the "Analog Signal Range" specification (±15V typical) and Figure 4 of the datasheet.

Does the DG425CY require external pull-up resistors on its control inputs (IN1, IN2, WR, RS)?

No, the DG425CY does not require external pull-up resistors. Its control inputs are CMOS/TTL-compatible with defined thresholds (VINH ≥ 2.4V, VINL ≤ 0.8V) and specify input currents of ±0.5µA max - low enough to be driven directly by microcontrollers or logic gates without added biasing. The datasheet shows functional operation with direct logic-level connections in Figures 2–3 and the truth tables.

Can the DG425CY operate with VL tied to V+ instead of a separate +5V supply?

Yes, the DG425CY can operate with VL connected to V+, but logic thresholds shift to CMOS levels (VIL ≈ 0.3×V+, VIH ≈ 0.7×V+), losing guaranteed TTL compatibility. For reliable 0.8V/2.4V thresholds, VL must be regulated at +5V. This distinction is explicitly stated in the "Logic Inputs" section and confirmed in the Electrical Characteristics table under "Input Current" test conditions.

What is the purpose of the N.C. pins (3, 4, 5, 6) on the DG425CY 16-pin SO package?

Pins 3, 4, 5, and 6 are No Internal Connection - they have no bond wires or die circuitry attached. Per Maxim's package drawings and pin descriptions, these pins must remain unconnected (floating) or optionally tied to GND for mechanical stability; routing traces or applying voltage risks parasitic coupling or EMI. This is documented in the "Pin Descriptions" section and "Pin Configurations" diagram.

How does the latch function of the DG425CY improve system reliability compared to non-latched analog switches?

The DG425CY's WR/RS latch architecture holds switch states independently of microprocessor bus activity, preventing unintended channel changes during interrupt service, bus contention, or power brownouts. This eliminates timing-critical strobing and removes dependency on sustained GPIO drive - a key advantage verified in the "Latch Timing" specifications (tWW = 200ns) and functional diagrams showing transparent/latched/reset modes.