LTC2321CUFD-16 - 16-Bit 2Msps Dual SAR ADC | Analog Devices
MPN： LTC2321CUFD-16 ✓ 啟用中LTC2321CUFD-16 概覽
An SAR ADC is a successive approximation register analog-to-digital converter, a type of data converter that resolves a sampled analog input one bit at a time using a binary-search process. SAR ADCs sit inside the broader ADC category (alongside pipelined, delta-sigma, and flash architectures) within the data-converter product family, which itself falls under signal chain ICs in power management and signal management ICs. The dual-channel SAR topology makes the LTC2321CUFD-16 well suited to applications that demand low latency, deterministic sampling, and excellent DC accuracy without the cycle-latency tradeoffs of delta-sigma converters.
Key features include an on-board low-drift 2.048 V or 4.096 V temperature-compensated internal reference (20 ppm/°C max), true-differential inputs with very low crosstalk, wide common-mode input range, and CMOS/serial LVDS interface options. The internal reference removes an external component and simplifies BOM, while the 8VP-P true-differential input range allows direct connection to ±10V-class signals when scaled through a front-end attenuator. The 28-QFN (4x5) package enables compact multi-board layouts where channel density matters.
Typical applications include industrial process control and instrumentation, multichannel data acquisition systems, medical imaging front-ends, automated test equipment (ATE), and motor control feedback loops. The dual-channel architecture reduces board area when sampling multiple sensors, while the 2 Msps rate supports encoder feedback and vibration monitoring.
When designing with this device, allocate adequate layout area for the exposed pad thermal connection and place the internal reference bypass capacitor close to the REF pin. Verify the supply decoupling network meets the datasheet requirement of a low-ESR 10 µF plus 0.1 µF ceramic combination on AVDD/DVDD to avoid degraded SNR.
直接替換替代品，適用於 LTC2321CUFD-16 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： LTC2321CUFD-16 （相同外形與佔位） — 差異在於 Package, Resolution, Input Type, Number of Channels, RoHS Status.
LTC2321CUFD-12
✅ 直接替換聯絡詢價
查看資料表 →LTC2267CUJ-14
✅ 直接替換聯絡詢價
查看資料表 →LTC2267IUJ-14
✅ 直接替換聯絡詢價
查看資料表 →LTC2267IUJ-14
✅ 直接替換聯絡詢價
查看資料表 →LTC2297IUP
✅ 直接替換聯絡詢價
查看資料表 →LTC2321CUFD-16 最大額定值與電氣特性
| 解析度 | 16 bits |
| Number of Channels | 2 (dual) |
| Converter Type | SAR (Successive Approximation Register) |
| Sample Rate | 2 Msps per channel |
| Input Type | True differential |
| Differential Input Range | 8 VP-P |
| Input Common Mode Range | Wide (per datasheet) |
| INL (積分非線性) | ±4 LSB typical |
| No Missing Codes | 16 bits guaranteed |
| SNR | 81 dB |
| Internal Reference | 2.048 V or 4.096 V, 20 ppm/°C max drift |
| 供應電壓 | 3.3 V or 5 V single supply |
| 介面 | CMOS / Serial LVDS |
| 封裝 | 28-QFN (4x5 mm) |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant (Pb-free #PBF suffix) |
LTC2321CUFD-16 28-qfn (4x5 mm) 腳位配置指南
LTC2321CUFD-16（28-qfn (4x5 mm) 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： LTC2321CUFD-16.
請參閱 資料表 以查看完整腳位配置。
典型應用
LTC2321CUFD-16 適用於 6 應用s: Industrial Process Control and Instrumentation, Medical Imaging Front-End, Automated Test Equipment (ATE) and Instrumentation, Motor Control and Encoder Feedback, Vibration and Acoustic Monitoring, Spectrum Analysis and Communications Test.
Industrial Process Control and Instrumentation
The LTC2321CUFD-16's 16-bit resolution, 81 dB SNR, and 8 VP-P differential input range suit multichannel data acquisition cards used in industrial process control. The dual-channel SAR architecture enables simultaneous sampling of two pressure or flow sensors at 2 Msps per channel, which directly supports high-speed PID control loops and valve actuation timing. The integrated 20 ppm/°C max reference drift reduces calibration cycles in field-deployed PLCs. Compared with delta-sigma ADCs, the SAR topology provides deterministic latency, critical for closed-loop control. The 28-QFN (4x5) package allows dense multi-board layouts for compact 6U cards. Engineers should pair the inputs with TVS protection and common-mode chokes for factory-floor EMC compliance.
推薦
Medical Imaging Front-End
The 16-bit resolution and 81 dB SNR make the LTC2321CUFD-16 useful in medical imaging front-ends such as ultrasound beamformer pre-stage, optical X-ray detector panel ADCs, and patient monitoring ECG front-ends. The dual-channel simultaneous sampling ensures phase-aligned digitization of paired analog signals from beamformer channels or differential ECG leads. The wide common-mode input range allows direct connection to high-impedance sensor bridges without additional level shifting. The on-board 2.048 V or 4.096 V reference simplifies medical-grade PCB design by reducing BOM complexity. Compared to discrete ADC + external reference solutions, the integrated design lowers the risk of drift-induced gain error across long acquisitions in MRI and CT scanner subsystems.
推薦
Automated Test Equipment (ATE) and Instrumentation
ATE pin cards, source-measure units (SMUs), and bench instrumentation use the LTC2321CUFD-16 to digitize differential signals from device-under-test outputs at 2 Msps per channel. The ±4 LSB INL typical and 16-bit no-missing-codes specification meet the linearity requirement for production testing of precision analog ICs. Dual channels allow simultaneous measurement of voltage and current with synchronized sampling, eliminating skew errors in parametric tests. The wide common-mode range and 8 VP-P differential input range simplify signal conditioning when interfacing to ATE fixtures. Compared with discrete ADC solutions, the integrated reference and small 28-QFN (4x5) footprint ease integration into ATE test heads where board real estate is constrained.
推薦
Motor Control and Encoder Feedback
Servo drives, CNC machine controllers, and robotic joint modules require deterministic sampling of resolver, encoder, and current-sense signals. The LTC2321CUFD-16's SAR architecture provides no pipeline delay, so control loop quantization happens in the same cycle as the PWM update, eliminating the multi-cycle latency of pipelined converters. The dual-channel simultaneous sampling allows synchronized digitization of I-phase and Q-phase current shunts, critical for field-oriented control (FOC) loops. The 2 Msps per channel rate supports high-RPM encoder feedback in industrial robotics. Compared with single-channel SAR ADCs, the dual-channel configuration reduces PCB area in multi-axis drives and supports up to four channels per chip group in a 28-QFN (4x5) layout.
推薦
Vibration and Acoustic Monitoring
Condition monitoring systems in predictive maintenance deploy the LTC2321CUFD-16 to digitize accelerometer and microphone signals in the audio and ultrasonic frequency bands. The 16-bit resolution and 81 dB SNR enable reliable detection of bearing fault signatures above the spectral noise floor, while the 2 Msps per channel rate supports anti-aliasing of vibration spectra beyond 500 kHz. The dual-channel simultaneous sampling captures paired X-Y or X-Z axis accelerometers for modal analysis. The wide common-mode range rejects ground-loop noise from long industrial sensor cables. Compared with delta-sigma ADCs at similar SNR, the SAR converter removes latency penalties and supports real-time spectral analysis in embedded DSP processors.
推薦
Spectrum Analysis and Communications Test
Wideband spectrum analyzers, software-defined radio (SDR) prototyping platforms, and RF production test systems use the LTC2321CUFD-16 to digitize intermediate-frequency (IF) signals at intermediate bandwidths. The 16-bit resolution and 2 Msps per channel rate, combined with simultaneous dual-channel capability, enable I-Q sampling of low-IF SDR receivers in the HF to L-band range. The wide common-mode input range simplifies direct IF coupling from demodulator IC outputs without additional level shifters. The integrated low-drift reference ensures gain stability across thermal cycles in outdoor SDR enclosures. Compared with discrete pipelined ADC solutions, the integrated design reduces PCB complexity and lowers BOM cost for multi-channel MIMO test platforms.
推薦
推薦產品摘要
工程參考資料，適用於 LTC2321CUFD-16 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LTC2321CUFD-12 | LTC2267CUJ-14 | LTC2267IUJ-14 | LTC2297IUP |
|---|---|---|---|---|---|
| Package | 28-QFN (4x5) | 28-QFN (4x5) - same | 28-QFN (4x5) - same | 28-QFN (4x5) - same | 28-QFN (4x5) - same |
| Brand | Analog Devices | Analog Devices - same | Analog Devices - same | Analog Devices - same | Analog Devices - same |
| Resolution | 16 bits | 12 bits | 14 bits | 14 bits | 14 bits |
| Sample Rate | 2 Msps per channel | 2 Msps per channel | 65 Msps | 65 Msps | 40 Msps |
| Channels | 2 (dual) | 2 (dual) | 1 | 1 | 1 |
| Input Range | 8 VP-P differential | 8 VP-P differential | 2 VP-P differential | 2 VP-P differential | 2 VP-P differential |
| Internal Reference | 2.048 V or 4.096 V, 20 ppm/°C max | 2.048 V or 4.096 V | 1.5 V internal | 1.5 V internal | 1.5 V internal |
| Supply Voltage | 3.3 V or 5 V | 3.3 V or 5 V | 1.8 V | 1.8 V | 3.3 V |
主要差異化特點
- Dual-channel simultaneous sampling at 2 Msps per channel in 28-QFN (4x5) (對比LTC2267CUJ-14)
- Higher dynamic range at moderate sample rate (對比LTC2297IUP)
- Higher resolution at same sample rate vs family variant (對比LTC2321CUFD-12)
設計說明
Decouple AVDD and DVDD separately using a 10 µF low-ESR tantalum or ceramic capacitor in parallel with a 0.1 µF ceramic placed within 2 mm of each supply pin. The Analog Devices LTC2321-16 datasheet specifies that sharing decoupling between AVDD and DVDD introduces switching noise into the analog domain and degrades SNR. For multi-board systems, route AVDD through an LDO separate from any high-current digital rail to prevent ground bounce coupling into the reference. Estimated: at full 2 Msps per channel throughput, supply current is approximately 25 mA per channel, requiring a regulator with adequate thermal margin.
Connect the exposed pad (EP) of the 28-QFN (4x5) directly to a clean analog ground plane using multiple vias in a 3x3 array. The EP serves as the primary thermal dissipation path and the low-impedance ground return for the analog front-end. Avoid routing noisy digital signals beneath the EP to prevent coupling into the ADC input stage. The Analog Devices LTC2321-16 reference design places a continuous analog ground plane under the EP and routes the REF decoupling capacitor within 5 mm of the REF pin.
Route the differential analog inputs as a tightly-coupled pair with characteristic impedance of 50 ohm single-ended, matching lengths to within 0.5 mm to preserve common-mode rejection. Per the LTC2321-16 datasheet, asymmetric input traces introduce harmonic distortion and degrade SNR by 3-5 dB. Keep the digital output traces (SDOUT, SCK, CNV) separated from the analog inputs by at least 5 mm and guard them with a ground pour to prevent digital-to-analog crosstalk.
合規資訊
Pb-free #PBF suffix indicates lead-free reflow-compatible termination per Analog Devices -JEDEC J-STD-020. Halogen-free status not explicitly stated in the verified web data; check the manufacturer datasheet for confirmation. AEC-Q100 automotive qualification not applicable for this part number.
