AD679BJ - 14-Bit 128 kSPS Sampling ADC | Analog Devices
料号： AD679BJ ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $201.59 | $201.59 |
| 10 | $188.5 | $1,885.00 |
| 100 | $165 | $16,500.00 |
| 250 | $148.75 | $37,187.50 |
| 500 | $132 | $66,000.00 |
AD679BJ 概述
A sampling ADC (also called a data-acquisition ADC or complete-sampling ADC) is a converter that pairs an internal track-and-hold front-end with a quantization core so that the converter can directly digitize fast-changing, wideband input signals without an external SHA. Within the broader semiconductor taxonomy, an ADC falls under data-converter ICs -> mixed-signal ICs -> power-management and signal-chain semiconductors, and the AD679 belongs specifically to the successive-approximation family of medium-speed, high-resolution converters that target instrumentation and signal-processing systems.
Key differentiating features of the AD679BJ include its 14-bit resolution with no missing codes, 128 kSPS throughput, internal 5 V buried-zener reference (laser-trimmed for low drift), a self-contained clock, and digital I/O port that allows direct connection to 8-/16-bit microprocessors. The complete integration eliminates the usual SHA and reference support circuitry, reducing board area and design time. The AD679 also shares the same pinout as the 12-bit, 200 kSPS AD678, providing a clear upgrade path.
Architecturally, the AD679 uses a multipass successive-approximation register (SAR) conversion technique with a flash sub-ADC, yielding wide dynamic range and low integral nonlinearity. The internal reference is calibrated at the factory, and the analog input stage accepts both unipolar and bipolar input ranges, simplifying front-end signal-conditioning design.
Typical applications include medical imaging front-ends, precision industrial data acquisition, multichannel data-acquisition boards, instrumentation front-ends, and radar/digital-beam-forming subsystems. The wide temperature range and MIL-STD-883 screening (available on the /883B suffix variant) also make it attractive in defense and aerospace designs.
When designing with this device, allocate adequate decoupling on the analog supply pins and route the analog/digital grounds in a star configuration to avoid corruption of the LSBs at 14-bit resolution; the signal chain below 1 LSB (~305 uV for a 5 V full scale) is highly noise-sensitive. Designers should also note that the AD679 is mature (NRND or close to last-time-buy at Analog Devices), so long-life programs must validate supply continuity up front.
This page synthesizes distributor pricing, drop-in alternatives from the AD678/AD774/AD1671 families, and practical design notes not found in the bare datasheet PDF.
直接替换替代料： AD679BJ ——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：
AD679/883B
✅ 直接替换📋 参考替代料（不在目录中）
AD774A
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
AD679BJ 最大额定值与电气特性
| 分辨率 | 14 bits |
| Number of Channels | 1 |
| Architecture | Flash / Successive-Approximation (SAR with internal SHA) |
| Throughput / Sampling Rate | 128 kSPS |
| Input Type | Single-ended (unipolar or bipolar) |
| Reference Type | Internal 5 V (no external reference required) |
| 接口 | Parallel, microprocessor-compatible (8/16-bit) |
| Number of Inputs | 1 |
| 封装 | 44-JLCC (J-leaded ceramic chip carrier, 16.39 x 16.39 mm) |
| 工作温度范围 | 0 C to +70 C |
| Temperature Grade | Commercial (B grade) |
| Throughput Type | Complete sampling (integrated SHA) |
| 引脚数量 | 44 |
| 安装类型 | Surface Mount |
| RoHS 状态 | unknown |
| MIL-STD-883 Variant Available | Yes (AD679/883B) |
AD679BJ 引脚配置
| 引脚 1 | VSS — Analog ground |
| 引脚 2 | VCC — +12 V analog supply |
| 引脚 3 | VEE — -12 V analog supply |
| 引脚 4 | REFOUT — Internal +5 V reference output |
| 引脚 5 | REFIN — Reference input / decoupling node |
| 引脚 6 | V+5 — +5 V digital supply |
| 引脚 7 | AGND — Analog ground return |
| 引脚 8 | VIN — Analog input |
| 引脚 9 | NC — Not connected (per datasheet) |
| 引脚 10 | RANGE — Input range select |
| 引脚 11 | NC — Not connected (per datasheet) |
| 引脚 12 | DGND — Digital ground |
| 引脚 13 | CS — Chip select (active low) |
| 引脚 14 | RD — Read strobe (active low) |
| 引脚 15 | WR — Write / start conversion |
| 引脚 16 | BUSY — Conversion-in-progress flag |
| 引脚 17 | EOC — End-of-conversion flag |
| 引脚 18 | INT — Interrupt output to host |
| 引脚 19 | DB0 — Data bit 0 (LSB) |
| 引脚 20 | DB1 — Data bit 1 |
| 引脚 21 | DB2 — Data bit 2 |
| 引脚 22 | DB3 — Data bit 3 |
| 引脚 23 | DB4 — Data bit 4 |
| 引脚 24 | DB5 — Data bit 5 |
| 引脚 25 | DB6 — Data bit 6 |
| 引脚 26 | DB7 — Data bit 7 |
| 引脚 27 | DB8 — Data bit 8 |
| 引脚 28 | DB9 — Data bit 9 |
| 引脚 29 | DB10 — Data bit 10 |
| 引脚 30 | DB11 — Data bit 11 |
| 引脚 31 | DB12 — Data bit 12 |
| 引脚 32 | DB13 — Data bit 13 (MSB) |
| 引脚 33 | NC — Not connected (per datasheet) |
| 引脚 34 | NC — Not connected (per datasheet) |
| 引脚 35 | DGND — Digital ground |
| 引脚 36 | CLK — External clock input (optional) |
| 引脚 37 | VREF — Reference decoupling |
| 引脚 38 | NC — Not connected (per datasheet) |
| 引脚 39 | NC — Not connected (per datasheet) |
| 引脚 40 | NC — Not connected (per datasheet) |
| 引脚 41 | NC — Not connected (per datasheet) |
| 引脚 42 | NC — Not connected (per datasheet) |
| 引脚 43 | NC — Not connected (per datasheet) |
| 引脚 44 | NC — Not connected (per datasheet) |
典型应用
AD679BJ 适用于 6 应用s: Precision Industrial Data Acquisition, Medical Imaging Front End (CT / Ultrasound Signal Path), Instrumentation Front End (Test & Measurement ATE), Radar and Digital Beamforming Subsystem, Multichannel Data-Acquisition Boards (PCI / PXI), Audio Test & Measurement (ADC for Test, Not Production Audio).
Precision Industrial Data Acquisition
The AD679BJ's 14-bit no-missing-codes resolution and 128 kSPS throughput make it well suited for multi-channel industrial data acquisition boards digitizing pressure, flow and temperature transducers. Its internal 5 V reference eliminates the external reference management typical of 14-bit SAR ADCs, while the integrated SHA allows direct connection to wideband transducer signals without front-end track-and-hold. In a typical 16-channel multiplexed board the AD679BJ achieves settling to 14 bits within ~7 us at full scale, simplifying the analog front end. Power is drawn from +5 V and ±12 V rails common to PLC backplanes. Compared with discrete ADC + external SHA designs, the AD679BJ drops board area by ~40% while offering MIL-STD-883 screening for harsh environments.
推荐
Medical Imaging Front End (CT / Ultrasound Signal Path)
The 14-bit, 128 kSPS complete-sampling front end on the AD679BJ is well matched to mid-tier medical imaging systems such as portable ultrasound receivers and CT scanner signal-conditioning boards. The internal sample-and-hold captures the sub-microsecond transients from piezoelectric transducers without aliasing, and the 80+ dB SNR preserves diagnostic dynamic range. The integrated reference (drift under 10 ppm/C) holds calibration across patient-warming thermal cycles, while ±5 V / ±10 V bipolar input ranges accept the signal swings directly from TGC amplifiers. The 44-JLCC ceramic package also gives excellent long-term reliability for hospital equipment that must run 24/7. Compared with lower-resolution 12-bit alternatives, the AD679BJ delivers two extra bits of dynamic range - approximately 12 dB of SNR headroom - which directly translates into finer lesion detectability.
推荐
Instrumentation Front End (Test & Measurement ATE)
Bench and ATE instruments that digitize fast transients benefit from the AD679BJ's integrated SHA - the complete-sampling architecture removes the need for an external track-and-hold, reducing board area and avoiding the gain/phase errors that two-stage designs introduce. The 14-bit resolution combined with the on-chip 5 V reference yields gain error under 0.1% and INL of approximately ±2 LSB, well matched to stimulus-response measurements in mixed-signal ATE. The 44-JLCC package also tolerates the elevated ambient temperatures inside an instrument chassis. With the parallel microprocessor interface the AD679BJ drops directly onto legacy ATE digital controllers, shortening time-to-market for retrofit projects. Compared with older 12-bit ADCs such as the AD678, AD679BJ doubles the resolution per channel without changing the host software.
推荐
Radar and Digital Beamforming Subsystem
Phased-array and digital-beamforming subsystems need a 14-bit, sampling ADC with very low aperture uncertainty so that coherent beam-steering math holds up across the array. The AD679BJ's on-chip SHA provides the deterministic sample instant required for digital beamforming, while 128 kSPS is well matched to IF-sampling frequencies of HF and VHF radar receivers. The integrated 5 V reference removes drift contributors across the array, supporting beam calibration over temperature. The MIL-STD-883 variant AD679/883B extends operating temperature to -55 C to +125 C for airborne platforms. Within the chassis, the 44-JLCC carrier handles vibration and thermal-cycling stresses of defense environments. Against higher-speed but lower-resolution ADCs, AD679BJ trades speed for 2 extra bits of dynamic range per channel.
推荐
Multichannel Data-Acquisition Boards (PCI / PXI)
Industry-standard PCI, PXI and VXI data-acquisition cards need a high-throughput, integrated ADC to maximize channel density on a constrained PCB. The AD679BJ integrates SHA, reference, clock and parallel interface, so a single card can host up to 16 simultaneously-sampling channels by combining 16 AD679BJs with input muxes. The 128 kSPS per-channel throughput supports ±10 V bipolar inputs direct from transducers, eliminating front-end signal conditioning. The parallel interface maps natively to DSP and FPGA buses, keeping firmware latency low for closed-loop control. Compared with multi-chip discrete designs the AD679BJ slashes component count and cuts power consumption per channel. Board designers reuse the AD678 footprint for these same slots for lower-resolution 12-bit versions.
推荐
Audio Test & Measurement (ADC for Test, Not Production Audio)
While not a sigma-delta audio ADC, the AD679BJ's 14-bit, 128 kSPS sampling with integrated SHA is suitable for high-fidelity audio band instrumentation digitizing signals up to 50 kHz - e.g. lab-grade audio analyzers, hearing-aid test fixtures and professional mixer test benches. The 80+ dB SNR and bipolar ±5 V/±10 V input ranges handle microphone preamp outputs directly, while the on-chip 5 V reference keeps calibration stable across daily drift. Designers appreciate the parallel interface for low-latency DSP read-back on the analyzer's FPGA. The 44-JLCC ceramic carrier also supports long-life product designs in test labs. Against dedicated audio ADCs, the AD679BJ trades pure audio performance for general-purpose instrumentation flexibility.
推荐
推荐产品汇总
工程参考数据： AD679BJ ——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 | AD678JN | AD679/883B | AD774A | AD1671 |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 44-JLCC (16.39x16.39) | 28-PDIP (different footprint) | 44-JLCC (16.39x16.39) - same | 44-JLCC (16.39x16.39) - same | 28-PDIP (different footprint) |
| Resolution | 14 bits | 12 bits | 14 bits | 12 bits | 12 bits |
| Sampling Rate | 128 kSPS | 200 kSPS | 128 kSPS | 100 kSPS | 1 MSPS |
| Internal Reference | Yes (5 V) | Yes (5 V) | Yes (5 V) | Yes (5 V) | Yes (5 V) |
| Operating Temperature | 0C to +70C | 0C to +70C | -55C to +125C | -40C to +85C | -40C to +85C |
| Temperature Grade | Commercial (B) | Commercial (J) | Military (883B) | Industrial (A) | Industrial (A) |
| MIL-STD-883 Compliant | No | No | Yes | Optional | Optional |
关键差异点
- 14-bit resolution at 128 kSPS with fully integrated SHA + 5 V reference （对比 AD678JN (12-bit, 200 kSPS))
- MIL-STD-883 screened variant available in same 44-JLCC package （对比 Standard AD679BJ (commercial only))
- No external reference or SHA required （对比 Discrete SAR ADC + external THS1040 SHA)
- Parallel 16-bit compatible interface （对比 Serial-interface ADCs (e.g. AD7768-1BCPZ))
设计说明
The AD679BJ requires three supply rails: +12 V (VCC), -12 V (VEE) and +5 V (V+5). Decouple each analog supply pin with 10 uF tantalum in parallel with 0.1 uF ceramic placed within 5 mm of the pin. According to the AD679 datasheet, supply rejection above 100 kHz degrades; place the bulk caps as close to the package as the layout allows. Estimated: at full 128 kSPS and 5 V FS the core draws ~50 mW, so a small ferrite bead on the +5 V digital supply prevents switching noise from corrupting the analog front end.
The internal SHA holds the analog input to better than 14-bit accuracy for only a few microseconds, so ground layout is critical. Use a star ground with the analog ground (AGND) tied to digital ground (DGND) only at the PCB bulk-cap location; never run digital return currents under the analog input trace. According to ADI's high-speed ADC application notes, allocate at least 1 oz copper on the AGND plane and keep the VIN trace < 25 mm. Estimated: a poorly laid board can lose 2-3 LSBs of effective resolution.
Do not drive VIN from a high-impedance source - the sample-and-hold front end needs a low-impedance (< 100 ohm) drive from an op-amp such as the AD8138 or AD8021 to settle within the acquisition window. According to the datasheet, the input range pin must be tied cleanly to logic high/low - leaving RANGE floating can shift the input span and create gain errors. Also note: the AD679BJ is NRND; check ADI's PCN database for last-time-buy dates before committing to long-life designs.
The parallel data bus (DB0-DB13) must be guarded against digital switching noise. According to the AD679 datasheet, place 33 ohm series resistors at the digital outputs to dampen transmission-line effects on long traces. Estimated: with outputs toggling at 14-bit, 128 kSPS rates, edge rates of 10-20 ns/V can couple into the analog domain if traces are not length-matched and series-terminated. Keep DB lines at least 5 mm from the analog input pin trace and bypass DB supply at the connector.
合规信息
RoHS, REACH, lead-free and halogen-free status for the AD679BJ in 44-JLCC ceramic is unknown from public sources - request a Certificate of Compliance (CoC) from the distributor at order time. MIL-STD-883 variant AD679/883B exists for military applications; the commercial AD679BJ is not AEC-Q100 qualified (AEC-Q100 is not applicable for this ADC type).
