DG445CJ+ - 85Ω Quad SPST Analog Switch | Analog Devices
料号： DG445CJ+ ✓ 量产中DG445CJ+ 概述
An analog switch is an integrated interface circuit that routes electrical signals between input and output terminals under digital control. The DG445 belongs to the analog-switch hierarchy, which also includes multiplexers, selectors, and signal-routing ICs. Unlike a mechanical relay, an analog switch changes connection state electronically with no mechanical movement. The DG445CJ+ combines four SPST switches in one package for applications requiring several independently controlled analog paths.
Key features include four 1:1 switching circuits, an 85Ω nominal on-resistance, low on-resistance variation between switches, and controlled flatness over the operating signal range. The 16-pin PDIP format supports conventional through-hole PCB assembly and is appropriate for prototypes, legacy equipment, and industrial control boards where a surface-mount package would complicate rework. The Analog Devices product page identifies the DG445 family as production-grade and describes its redesigned switch matching characteristics.
The matched on-resistance specification reduces channel-to-channel gain variation when identical signals are routed through different switches. A maximum matching of 4Ω and flatness of 9Ω are particularly relevant when the same measurement or control path must behave consistently across multiple inputs. These characteristics can simplify calibration and improve repeatability in data-acquisition, test-equipment, and control systems.
Typical applications include sensor-signal routing, sample-and-hold front ends, instrumentation multiplexing, industrial control interfaces, and precision measurement systems. Four independent SPST switches allow one controller to select test paths, isolate stages, or route external analog signals without changing the printed-circuit-board layout. The device is especially useful where four similar channels must have closely matched resistance behavior.
PCB design should preserve the pin assignments and pin numbering defined by the manufacturer datasheet. Because the package is a PDIP-16, adequate lead spacing and through-hole clearance are required, while analog input and output routing should minimize coupling from adjacent switching or digital-control nets. The control inputs should be driven with compatible logic levels, and unused or inactive channels should be configured according to the device data sheet.
This product page combines the DG445CJ+ configuration, package information, matched-resistance characteristics, application guidance, and cross-reference analysis with practical design context. It supports faster part selection by showing where the quad SPST architecture fits and where a verified drop-in substitute may be appropriate.
直接替换替代料： DG445CJ+ ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： DG445CJ+ （相同外形与封装尺寸） ——差异在于 Switch Configuration, Number of Channels.
DG445CJ+ 最大额定值与电气特性
| Number of Switches | 4 circuits |
| Switch Configuration | 1:1 |
| Switch Type | Single-pole single-throw (SPST) |
| Nominal On-Resistance | 85 Ω |
| On-Resistance Matching | 4 Ω maximum between switches |
| On-Resistance Flatness | 9 Ω maximum over the signal range |
| Number of Terminals | 16 terminals |
| 封装 | 16-pin PDIP |
| Package Outline | MS-001-AA |
| 安装类型 | Through-hole |
| Process Technology | CMOS |
| Temperature Grade | Commercial |
| Production Status | Production |
| Product Family | Improved, quad, SPST analog switches |
| Number of Functions | 4 functions |
| Number of Channels per Switch | 1 channel |
DG445CJ+ ms-001-aa 引脚配置指南
DG445CJ+（ms-001-aa 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： DG445CJ+.
请参阅 数据手册 以查看完整引脚配置。
典型应用
DG445CJ+ 适用于 6 应用s: Sensor Signal Routing, Precision Data Acquisition, Industrial Control Signal Isolation, Automated Test Equipment, Audio and Communication Routing, Calibration Signal Distribution.
Sensor Signal Routing
The DG445CJ+ fits sensor-front-end designs that must route several low-level analog inputs through similar signal paths. Its four SPST switches provide independent 1:1 connections, while the 4Ω maximum on-resistance matching limits channel-to-channel resistance variation. The 9Ω maximum flatness specification helps maintain consistent behavior across the signal range. Because the nominal on-resistance is 85Ω, source impedance and downstream amplifier loading must be included in the gain-error calculation. A practical implementation assigns one switch to each sensor or calibration path and drives the control inputs from a controller while keeping sensitive analog traces short and away from digital return paths.
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Precision Data Acquisition
The DG445CJ+ can connect multiple analog inputs to a measurement channel when repeatable switch resistance is important. Four matched SPST paths reduce uncertainty from switch-to-switch variation, with on-resistance matching specified at 4Ω maximum and flatness at 9Ω maximum across the signal range. The 85Ω nominal resistance must be included when calculating source-loading error, particularly with high-impedance sensors. Designers can place the switches close to the ADC input or sensor junction, then use matched routing and guarding to minimize leakage and coupling. Its four-channel architecture also provides enough routing flexibility to select measurement, reference, and calibration inputs without a separate relay for each path.
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Industrial Control Signal Isolation
The DG445CJ+ is appropriate for industrial control boards that route analog command or feedback signals while preventing cross-connections between selected channels. Each of its four SPST switches provides a direct 1:1 path, and the family’s controlled resistance matching supports repeatable behavior across controlled channels. The 85Ω nominal on-resistance may be acceptable for low-current control and measurement signals, but it can create measurable attenuation with high-impedance receivers. Industrial implementations should use protective grounding, current limiting, and appropriate surge protection at exposed interfaces. Locating the device near the connector or sensing network helps reduce susceptibility to board-level coupling and improves routing flexibility.
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Automated Test Equipment
The DG445CJ+ supports automated test-equipment matrices where several test paths must be selected under software control. Its four independent SPST switches can route test stimuli, sense returns, or reference signals without mechanical relay switching. Matching of 4Ω maximum and flatness of 9Ω maximum reduce path-dependent error when repeated measurements move among similar channels. The 85Ω nominal on-resistance should be included in the calibration model for high-impedance DUTs, while the low switching resistance is usually less significant for low-impedance fixtures. Placing the switches near test nodes and separating control traces from sensitive returns helps preserve measurement repeatability across automated test sequences.
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Audio and Communication Routing
The DG445CJ+ can route moderate-bandwidth analog signals in communication and audio equipment when four controlled paths are needed. The 85Ω nominal on-resistance is higher than a low-impedance audio switch, so it is better suited to line-level, microphone-bias, or buffered inputs than to demanding high-current speaker outputs. Channel matching of 4Ω maximum can limit gain differences across equivalent routes. Designers should place the device near the source or receiver, maintain a continuous ground reference, and avoid sharing sensitive return paths with digital switching currents. Input and output protection should be selected according to the maximum signal amplitude and interface environment.
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Calibration Signal Distribution
The DG445CJ+ can distribute or isolate calibration signals to multiple measurement channels. Matching of 4Ω maximum and on-resistance flatness of 9Ω maximum are useful because a reference signal should undergo similar attenuation when routed through different switches. The 85Ω nominal resistance still forms part of the divider formed with source and load impedances, so calibration tables should reflect the actual operating path. A robust design uses a low-impedance reference source, measures the selected channel where possible, and keeps the four analog paths symmetrical. Digital control traces should be referenced cleanly to minimize injected charge that could disturb high-impedance calibration nodes.
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推荐产品汇总
工程参考数据： DG445CJ+ ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | DG442DJ | DG444CJ+ |
|---|---|---|---|
| Package | 16-pin PDIP | 16-pin PDIP - same | 16-pin PDIP - same |
| Brand | Analog Devices / Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Switch Configuration | Quad SPST | SPST | Quad SPST |
| Mounting Type | Through-hole | Through-hole | Through-hole |
关键差异点
- Tighter guaranteed resistance matching （对比 DG444CJ+)
- Lower nominal insertion resistance （对比 DG444CJ+)
- Guaranteed flatness over the signal range （对比 DG442DJ)
设计说明
Use the manufacturer’s MS-001-AA package drawing to define hole diameter, row spacing, and pin clearance instead of relying on a generic DIP footprint. Keep the four switched analog paths short and place the DG445CJ+ close to the connector, sensor, or receiver that uses the selected signal. Separate control inputs from analog returns and route a continuous ground reference beneath or adjacent to the analog section to reduce injected coupling.
Include the 85Ω nominal on-resistance in the gain and attenuation calculation for every connected source and load impedance. For high-impedance sensors, the switch and amplifier input form a divider that can dominate the error budget. The 4Ω maximum matching and 9Ω maximum flatness specifications limit variation between channels, but they do not eliminate the nominal resistance. Buffer high-impedance sources before the switch when lower insertion resistance is required.
Do not assume that every DIP-16 analog switch has the same pin functions, control polarity, or electrical limits. Compare the DG445CJ+ pin-description table with the selected replacement and verify supply voltage, input and output ratings, switch logic, and maximum signal current. A mechanically similar footprint is not sufficient for a safe substitution. Confirm the exact ordering code and package form before releasing a production order.
合规信息
The DG445CJ+ is a commercial-grade CMOS interface IC. No specific RoHS, REACH, halogen-free, or conflict-minerals declaration was established for this ordering code, so those fields remain unknown.