AD678KD - 12-Bit 200 kSPS Sampling ADC | Analog Devices
料号： AD678KD ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $134.8715 | $134.87 |
| 10 | $134.8715 | $1,348.72 |
| 100 | $134.8715 | $13,487.15 |
| 500 | $134.8715 | $67,435.75 |
| 1,000 | $134.8715 | $134,871.50 |
AD678KD 概述
What is a complete sampling ADC? A sampling ADC captures an analog voltage with an internal sample-and-hold amplifier and converts that sample into a digital code. The AD678 belongs to the ADC hierarchy and integrates the sampling, conversion, reference, clock, and digital-interface functions needed for direct signal acquisition. This integration reduces the number of external components and makes the converter suitable for instrumentation, industrial control, communications, and measurement systems.
Key verified characteristics include 12-bit resolution, 200 kSPS operation, one analog input, flash architecture, parallel output, and a 28-pin CDIP/SBCDIP package. The AD678 is specified for dynamic parameters including signal-to-noise-plus-distortion ratio, total harmonic distortion, and intermodulation distortion. Those parameters are particularly relevant when the converter handles waveform acquisition or other signal-processing applications.
The device also includes a voltage reference and clock-generation circuitry, allowing it to operate as a more complete acquisition element than a bare flash-converter core. The Analog Devices product page states that the AD678 provides the same pinout as the 14-bit, 128 kSPS AD679 ADC, creating a documented upgrade path when a design requires related interface geometry and higher resolution at a lower sampling rate.
Typical uses include dynamic signal measurement, process monitoring, communications equipment, laboratory instrumentation, and industrial data-acquisition systems. The 200 kSPS rate is suitable for many high-speed measurement tasks, while the 12-bit code width establishes the digital resolution available to downstream processors.
A key design consideration is the distinction between a verified product-family relationship and a true drop-in replacement. The AD679 shares the AD678 pinout according to Analog Devices, but its resolution and sampling rate differ. Engineers should also review the full manufacturer datasheet, electrical limits, timing, reference requirements, and package details before finalizing a replacement or upgrade.
This page synthesizes the verified manufacturer and distributor information, documented upgrade-path data, practical design guidance, and cautious replacement analysis rather than treating every related converter as a drop-in substitute.
直接替换替代料： AD678KD ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
AD679
✅ 直接替换📋 参考替代料（不在目录中）
AD678
✅ 直接替换📋 参考替代料（不在目录中）
AD678KD 最大额定值与电气特性
| 分辨率 | 12 bit |
| 采样率 | 200 kSPS |
| Input Count | 1 input |
| Architecture | Flash |
| Output Interface | Parallel |
| 封装 | 28-pin CDIP/SBCDIP |
| 安装类型 | Through Hole |
| Integrated Functions | Sample-and-hold amplifier, microprocessor-compatible bus interface, voltage reference, and clock-generation circuitry |
| Input Type | Single-ended |
| Voltage Reference | Internal voltage reference |
| Clock Generation | Internal clock-generation circuitry |
| MIL-STD-883 Version | Available in compliant versions |
AD678KD 28-pin cdip/sbcdip 引脚配置指南
AD678KD（28-pin cdip/sbcdip 封装）的引脚配置。 该模拟元件具有输入、输出和电源引脚。请参阅制造商数据手册以了解失调调零、补偿和使能引脚配置。适用于信号调理和放大器电路。
暂无详细引脚数据： AD678KD.
请参阅 数据手册 以查看完整引脚配置。
典型应用
AD678KD 适用于 6 应用s: Dynamic Signal Acquisition, Industrial Process Monitoring, Communications Receiver Front End, Laboratory Measurement Equipment, Data-Acquisition Control Cards, Waveform Monitoring.
Dynamic Signal Acquisition
The AD678KD fits dynamic signal-acquisition systems that need a complete 12-bit converter rather than a bare ADC core. Its verified 200 kSPS sampling rate provides a defined conversion rate, while the integrated sample-and-hold amplifier, voltage reference, and clock-generation circuitry reduce external support requirements. The parallel output can feed a microprocessor, FPGA, or digital signal-processing system without a serial-interface conversion stage. Designers should confirm acquisition time, input bandwidth, and exact SNR+D, THD, and IMD limits in the manufacturer datasheet for the particular signal amplitude and sampling frequency.
推荐
Industrial Process Monitoring
AD678KD can be used in industrial process-monitoring equipment when sensor outputs must be digitized for supervisory control, logging, or alarm decisions. The single-input, 12-bit architecture is appropriate for many slow-to-moderate process signals, and the 200 kSPS capability provides margin for sampling multiple acquisition sequences around a measurement event. The integrated reference and clock circuitry can simplify the analog front end, but grounding, isolation, input protection, and calibration remain important. Use the exact manufacturer electrical limits to select input conditioning and ensure the selected controller can latch the parallel output reliably.
推荐
Communications Receiver Front End
AD678KD may suit communications or IF-signal measurement blocks where a parallel ADC output and integrated sampling functions simplify interface timing. Its 200 kSPS sampling rate makes it useful for selected envelope, waveform, or intermediate-frequency measurement paths, although it is not characterized here as a high-frequency RF converter. The design should verify input bandwidth, aliasing, dynamic range, and acquisition settling against the exact datasheet values. A sampling clock and digital processor must be synchronized carefully to avoid timing errors or repeated-conversion artifacts.
推荐
Laboratory Measurement Equipment
AD678KD is a practical candidate for laboratory instruments that acquire repeatable waveforms and perform digital filtering, statistics, or compensation in a downstream processor. Its 12-bit resolution gives a defined code width, while the integrated voltage reference and sample-and-hold amplifier help establish a consistent measurement chain. The 200 kSPS rate is suitable for many general-purpose measurement channels, but accuracy depends on input conditioning, reference behavior, source impedance, and PCB layout. Verify the package's through-hole pinout and thermal limits in the manufacturer datasheet before creating a new board.
推荐
Data-Acquisition Control Cards
AD678KD can be used in a data-acquisition card where a controller must receive sampled values over a parallel bus. The converter's single-input organization simplifies multiplexing when paired with an external analog switch, while its complete sampling architecture avoids the need for a separate sample-and-hold stage in a basic channel. Because AD678KD is a 28-pin through-hole device, designers should preserve the documented footprint and pin numbering in legacy control-card designs. Check acquisition timing, input settling, logic levels, and software scaling against the final system clock.
推荐
Waveform Monitoring
AD678KD is suitable for waveform-monitoring tasks that require moderate conversion speed and a parallel digital result, such as sampling a conditioned sensor waveform for peak, RMS, or spectral analysis. The 200 kSPS verified rate supports repeated samples at a known cadence, while 12-bit resolution provides 4096 digital code levels. The exact usable bandwidth is not established by the supplied snippets, so anti-alias filtering and front-end gain must be designed from the manufacturer specifications. The integrated reference and clock circuitry can simplify calibration, but system-level offset and gain error still require validation.
推荐
推荐产品汇总
工程参考数据： AD678KD ——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 | AD679 | AD678 |
|---|---|---|---|
| Package | 28-pin CDIP/SBCDIP | 28-pin CDIP/SBCDIP; same documented pinout | 28-pin CDIP/SBCDIP; family/order-code verification required |
| Brand | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 12 bit | 14 bit | 12 bit |
| Sampling Rate | 200 kSPS | 128 kSPS | 200 kSPS |
关键差异点
- Documented same-pinout family upgrade path （对比 AD679)
- Higher verified conversion rate than the AD679 comparison （对比 AD679)
- Complete integrated conversion chain （对比 AD679)
设计说明
Begin with the manufacturer datasheet's supply-voltage and power-consumption limits; those values were not included in the supplied snippets. Because AD678KD integrates a voltage reference, sample-and-hold amplifier, and clock circuitry, the analog and digital supply rails must still be decoupled according to the datasheet layout guidance. Keep the reference and input paths away from high-current digital return paths, and verify that the controller's supply sequence does not violate the ADC's input limits.
Route the analog input, reference, and sample-and-hold-related connections away from the 12-bit parallel output bus. Keep the through-hole footprint and pin numbering consistent with the official AD678 datasheet; do not infer pin names from the AD679 relationship alone. Provide a clean return path beneath or around the converter, use short digital traces where practical, and place any external input protection or filtering close to the source while preserving the required acquisition bandwidth.
Do not treat the AD679 as an electrically identical replacement merely because Analog Devices states that the AD678 and AD679 have the same pinout. AD679 is documented as 14-bit and 128 kSPS, while AD678KD is 12-bit and 200 kSPS. Software code scaling, conversion timing, latency assumptions, and downstream filter behavior may change. Confirm the complete AD679 electrical specification and verify the exact PCB pinout before approving the substitution.
The parallel output bus creates a timing and grounding concern at the system level. Match the controller and ADC logic requirements, account for output timing and setup/hold margins, and avoid loading the outputs beyond the manufacturer's limits. If the acquisition clock is generated or distributed on the same board, separate clock routing from sensitive analog paths and evaluate crosstalk experimentally. Exact timing values are unavailable in the supplied data and must be taken from the manufacturer datasheet.
合规信息
The supplied verified data states that AD678 versions are available compliant with MIL-STD-883, but it does not provide a definitive RoHS, REACH, lead-free, halogen-free, or conflict-minerals declaration for AD678KD. A comparison snippet lists RoHS as NN, but that field is not treated as an authoritative compliance statement.
