Vishay Siliconix DG445BDY

Overview

DG445BDY from Vishay Siliconix is a quad SPST CMOS analog switch with complementary logic control (ON when IN = 0 V), 45 Ω typical on-resistance at ±15 V supplies, 120 ns typical turn-on time, and <1 pC charge injection - designed for precision sample-and-hold circuits, data acquisition front-ends, and low-distortion audio routing.

For engineers reviewing the DG445BDY datasheet, DG445BDY pinout, DG445BDY application, or DG445BDY equivalent, this page delivers verified electrical parameters, SOIC-16 package mapping, functional truth table alignment, and real-world design context for signal integrity-critical analog switching.

Technical Context

The DG445BDY implements four independent bidirectional analog switches with TTL/CMOS-compatible digital inputs referenced to VL (logic supply) and dual ±15 V analog rails. Its silicon-gate process ensures latchup immunity via epitaxial isolation, and each channel blocks signals beyond V+ or V− using internal clamping diodes.

Unlike the DG444B, the DG445BDY inverts logic polarity: logic low (≤0.8 V) enables conduction, while logic high (≥2.4 V) disables all switches. This inversion supports direct interface with active-low control buses and simplifies level-shifting in mixed-supply systems.

Key Specifications

Pinout & Package

Package: 16-pin narrow-body SOIC (JEDEC MS-012), 3.9 mm × 9.9 mm footprint, 1.27 mm pitch, 1.75 mm max height.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DG445BDY, MAX4617ESE+ trades higher on-resistance and charge injection for broader temperature range (−40°C to +125°C), while ADG1414BRUZ delivers 10× lower on-resistance and 5× lower charge injection but mandates 3 V logic interfacing - making DG445BDY optimal for 5 V-controlled, ±15 V, cost-sensitive 12–14 bit DAQ and audio systems.

Availability

DG445BDY is available at Aetrix Electronics and suitable for data acquisition systems, medical instrumentation, and audio signal routing requiring stable component supply, long-term lifecycle support, and traceable sourcing from Vishay-authorized channels.

Supply support for DG445BDY 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

Vishay Siliconix designs high-reliability discrete semiconductors and analog ICs, specializing in power MOSFETs, diodes, optoelectronics, and precision analog switches for industrial, automotive, and computing markets.

The DG445BDY belongs to Vishay's high-speed analog switch family engineered for low-error signal routing in test equipment, medical devices, and communication infrastructure where on-resistance flatness, charge injection, and supply robustness are critical.

FAQ

What is the logic polarity of DG445BDY compared to DG444BDY?

The DG445BDY uses inverted logic: a logic low (≤0.8 V) on INx turns the corresponding switch ON, while a logic high (≥2.4 V) turns it OFF. In contrast, DG444BDY activates on logic high. This difference is hardwired in silicon and cannot be changed externally - correct logic polarity must be matched in system firmware or hardware control lines to avoid unintended switching behavior in DG445BDY.

Can DG445BDY operate with a single +12 V supply instead of dual ±15 V?

Yes, DG445BDY supports unipolar operation: V+ = +12 V, V− = 0 V, VL = +5 V. In this configuration, the analog signal range is 0 V to +12 V, R_DS(on) increases to 90 Ω typ., and t_ON remains 120 ns typ. The device retains full functionality, but designers must ensure all analog signals stay within 0 V to +12 V and that GND is referenced to V− to maintain proper biasing of internal protection diodes.

How does DG445BDY prevent latchup in high-voltage applications?

DG445BDY incorporates an epitaxial layer in its silicon-gate process that electrically isolates the CMOS control circuitry from the analog switch channel. This structure prevents parasitic SCR formation under transient overvoltage or rapid supply ramp conditions - verified up to ±22 V on V+ or V− pins. No external latchup protection components are needed, simplifying design for industrial environments with noisy power rails.

What is the maximum recommended PCB trace length between DG445BDY and its 1 nF hold capacitor in sample-and-hold designs?

For minimal charge injection error and aperture jitter, PCB traces between DG445BDY drain pins and the hold capacitor should be ≤5 mm in length and routed away from digital switching noise sources. Longer traces increase stray capacitance and inductance, degrading the 1 pC charge injection spec and causing >10 mV pedestal error in 1 µs hold cycles - verified in Vishay Application Note 826 layout guidelines for precision S/H circuits using DG445BDY.

Does DG445BDY require external pull-up or pull-down resistors on its digital inputs?

No, DG445BDY digital inputs have TTL/CMOS-compatible thresholds (V_INL ≤ 0.8 V, V_INH ≥ 2.4 V) and draw ≤1 µA input current - allowing direct connection to microcontroller GPIO, FPGA I/O banks, or logic gates without external biasing. Pull-up/pull-down resistors are unnecessary unless the driving source has high-impedance or open-drain outputs, in which case a 10 kΩ pull-up to VL is recommended for noise immunity.