DG445DJ+ - Quad SPST 85 Ohm Analog Switch | Analog Devices
MPN: DG445DJ+ ✓ ActiveDG445DJ+ Overview
An analog switch is a semiconductor device that uses digital control signals to connect or disconnect an analog signal path. The DG445DJ+ belongs to the interface-IC hierarchy as a monolithic CMOS analog switch. Its four independent SPST channels provide normally open behavior, allowing a control signal to establish a signal connection while the open state provides high isolation between routed nodes.
The verified manufacturer information identifies the DG445 family as an improved replacement for the DG211 and DG212 series. It provides four independent switches, TTL- and CMOS-compatible digital inputs, on-resistance matching of 4 ohms maximum between switches, and guaranteed on-resistance flatness of 9 ohms maximum across the signal range. The distributor listing specifies an 85 ohm nominal on-resistance, while a legacy data listing reports 50 ohms; the 85 ohm figure is used for the DG445DJ+ procurement description.
The improved matching and flatness specifications are significant when several DG445DJ+ channels carry signals that must present similar resistance to downstream circuitry. Flatness limits resistance variation as the analog voltage changes, helping preserve gain and timing consistency across the signal range. The monolithic CMOS implementation supports compact analog-routing designs without requiring four discrete mechanical or relay elements.
Typical uses include battery-powered measurement systems, automated test equipment, multiplexed sensor interfaces, audio routing, sample-and-hold circuits, and communication equipment. Each of the four switches has its own control input, allowing independent routing decisions rather than requiring a shared address decoder. The 16-pin PDIP package is suitable for prototyping, legacy industrial equipment, and through-hole assemblies.
The principal design consideration is that this older PDIP device is identified as RoHS non-compliant and contains lead. It should therefore be selected for compatible legacy or through-hole applications where regulatory and thermal requirements permit, rather than assumed suitable for new lead-free production without formal review.
This product record combines verified manufacturer and distributor specifications, lifecycle information, pricing, package details, and practical selection guidance. It also distinguishes confirmed drop-in information from unsupported substitute claims, helping engineers avoid cross-package parts that would require PCB changes.
Drop-in alternatives for DG445DJ+ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with DG445DJ+ (same form factor and footprint) — differing in Switch Configuration.
DG445DJ
✅ Drop-In📋 Reference alternative (not in catalog)
DG445DJ+ Maximum Ratings & Electrical Characteristics
| Number of Switches | 4 independent switches |
| Switch Configuration | 1:1 SPST |
| Switch State | Normally open |
| On-Resistance | 85 ohm |
| On-Resistance Matching Between Switches | 4 ohm maximum |
| On-Resistance Flatness Over Signal Range | 9 ohm maximum |
| Logic Compatibility | TTL and CMOS compatible |
| Technology | Monolithic CMOS |
| Package | 16-pin PDIP |
| Package Body Style | MS-001-AA |
| Lifecycle Status | Production |
| RoHS Status | Non-compliant |
| Lead-Free Status | Contains lead |
| Manufacturer Reference Document | DG445 Data Sheet, Rev. 4 |
| Manufacturer List Price From | 3.48 USD |
DG445DJ+ ms-001-aa Pin Configuration Guide
Pin configuration for DG445DJ+ (ms-001-aa package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for DG445DJ+.
Refer to the datasheet for full pin configuration.
Typical Applications
DG445DJ+ is suitable for 6 applications: Automated Test Equipment Signal Routing, Battery-Powered Sensor Interfacing, Audio Signal Routing, Sample-and-Hold and Measurement Systems, Communication Equipment Signal Isolation, Industrial Control and Legacy Equipment.
Automated Test Equipment Signal Routing
The DG445DJ+ fits automated test equipment that requires four independent analog connections under software control. Its four normally open SPST channels can route a source, return, stimulus, or measurement path without adding a shared multiplexer decoder. The family-level on-resistance matching of 4 ohms maximum helps limit channel-to-channel measurement variation, while 9 ohms maximum flatness reduces resistance changes across the signal range. Use the 16-pin PDIP package for through-hole instrument boards and verify the exact terminal drawing before layout. Compared with mechanical relays, the monolithic CMOS design enables faster, compact routing, but the 85 ohm nominal resistance remains important when designing low-impedance source paths or precision divider networks.
Recommended
Battery-Powered Sensor Interfacing
The DG445DJ+ is suitable for battery-powered sensor interfaces that must connect several low-frequency analog inputs to a shared measurement circuit. Four independently controlled SPST paths can isolate sensors, select a reference, or route excitation and return lines. The TTL- and CMOS-compatible controls permit use with common digital logic, while the on-resistance matching of 4 ohms maximum helps maintain more consistent channel behavior across a sensor array. The 85 ohm nominal on-resistance should be included in the sensor-source impedance calculation because it can affect accuracy when driving high-impedance inputs. Its PDIP format is practical for low-volume instrumentation, though the verified lead-containing status requires a separate compliance review for new portable products.
Recommended
Audio Signal Routing
The DG445DJ+ can route four independently controlled low-level audio signals in legacy mixer, monitor, or test equipment. Its normally open SPST topology provides a simple muting or source-selection function, while the 4 ohm maximum resistance matching helps reduce output imbalance when multiple channels feed comparable circuitry. The 9 ohm maximum on-resistance flatness across the signal range is relevant to audio signals because resistance changes can alter level, damping, and frequency response. With an 85 ohm nominal on-resistance, the device is best placed before a high-impedance audio stage rather than directly in a low-impedance speaker path. The 16-pin PDIP package also simplifies repair and retrofit work in older analog equipment.
Recommended
Sample-and-Hold and Measurement Systems
The DG445DJ+ supports sample-and-hold and general measurement systems requiring four controlled analog paths. Independent SPST switches can isolate a signal during acquisition, connect a reference during calibration, or route between measurement and instrumentation nodes. The family’s 4 ohm maximum on-resistance matching and 9 ohm maximum flatness provide useful consistency when several channels are compared. Designers must account for the 85 ohm nominal series resistance, switch leakage, control timing, and any charge injection using the complete manufacturer datasheet. The PDIP package is advantageous for legacy laboratory equipment and easily serviced analog boards, but its lead-containing construction should be reviewed before use in new regulated or RoHS-scoped production.
Recommended
Communication Equipment Signal Isolation
The DG445DJ+ can provide signal isolation and path selection in communication equipment where four low-frequency analog lines must be switched independently. Normally open SPST channels can disconnect inactive sources, reduce unintended signal coupling, and simplify fault isolation during diagnostics. The 4 ohm maximum matching between switches is useful when the routed signals feed similarly terminated receiver circuitry, while the 9 ohm maximum flatness limits variation over the operating signal range. Because the specified nominal resistance is 85 ohm, designers should avoid placing it in a high-current drive path and should assess insertion loss at the relevant frequency. Its through-hole PDIP construction makes it appropriate for legacy line-card and interface-board maintenance after verifying supply and logic compatibility.
Recommended
Industrial Control and Legacy Equipment
The DG445DJ+ is appropriate for industrial control and legacy equipment where a controller must select among several analog or instrumentation lines. Its four independent channels and TTL- and CMOS-compatible inputs allow direct use with suitable control logic, while the 85 ohm on-resistance should be checked against the impedance of the connected sensor or actuator interface. The 16-pin PDIP package remains convenient for through-hole maintenance, test fixtures, and equipment designed before compact surface-mount packages became standard. Because the verified DG445DJ documentation identifies the family as containing lead and not RoHS compliant, engineers should retain the part only where regulatory policy and the finished equipment’s compliance strategy permit it, and preserve traceable sourcing for repair inventory.
Recommended
Recommended Products Summary
Engineering reference data for DG445DJ+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | DG445DJ |
|---|---|---|
| Package | 16-pin PDIP | 16-pin PDIP - same |
| Brand | Analog Devices | Analog Devices |
| Switch Count | 4 | 4 |
| Switch Configuration | SPST, 1:1 | SPST, 1:1 |
| Nominal On-Resistance | 85 ohm | 85 ohm |
| Technology | Monolithic CMOS | Monolithic CMOS |
Key Differentiators
- Four independently controlled channels (vs Single-channel or multiplexed routing designs)
- Improved channel resistance matching (vs DG211 and DG212 predecessor families)
- Guaranteed resistance flatness (vs Legacy DG445DJ listing without a supplied matching or flatness guarantee)
Design Notes
Include the 85 ohm nominal on-resistance and the family limits of 4 ohms maximum matching and 9 ohms maximum flatness in the signal-path budget. If a path drives a high-impedance amplifier, account for the resistance with the amplifier input impedance; if it drives a lower-impedance node, check divider attenuation and capacitive charging speed before relying on the switch. Use the manufacturer’s matching and flatness curves when the signal amplitude is not small relative to the supply rails.
Lay out the DG445DJ+ in a 16-pin through-hole pattern based on the ordering-code-specific MS-001-AA drawing. Place it away from high-current switching nodes and analog sources that could couple noise through the control or power pins. Maintain a low-impedance return for the control reference, keep sensitive analog traces away from digital control routing where practical, and check the exact pin names against the datasheet because the supplied excerpts do not provide a complete terminal table.
Do not treat DG441DJ+ as a drop-in substitute merely because it also uses a quad-SPST architecture. The verified comparison lists DG441DJ at 160 ohm versus 85 ohm for DG445DJ+, an approximately 88% resistance difference, so it is excluded from the alternatives list. Likewise, the DG444 family may differ in switch polarity; confirm normally open or normally closed behavior rather than relying only on the 16-pin package outline.
The supplied excerpts do not provide complete supply-voltage, quiescent-current, or control-input-current limits. Before energizing the device, verify those values in the DG445 Data Sheet, Rev. 4 and ensure every control signal remains within its permitted logic range. Power sequencing should also be checked so that the analog supply and control logic do not violate absolute-maximum conditions during power-up, power-down, or repair operations.
Compliance Information
The verified DG445DJ specifications identify the part as RoHS non-compliant and containing lead. No verified REACH, halogen-free, conflict-minerals, or automotive-qualification statement was supplied.