LTC2344CUH-18 - 18-Bit 400kSPS Quad SAR ADC | Analog Devices
部品番号: LTC2344CUH-18 ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $28.5 | $28.50 |
| 10 | $25.65 | $256.50 |
| 100 | $22.8 | $2,280.00 |
| 500 | $20.5 | $10,250.00 |
| 1,000 | $18.2 | $18,200.00 |
LTC2344CUH-18 概要
A successive approximation register (SAR) ADC is a precision data converter architecture that resolves one bit per clock cycle using a binary-weighted capacitor DAC and a comparator, then digitizes the input through a successive approximation search. SAR ADCs are valued for low latency, deterministic behavior, no pipeline latency, and excellent DC accuracy. Within the converter family hierarchy, SAR ADCs sit below pipelined ADCs (higher speed, higher channel count) and delta-sigma ADCs (highest resolution, lowest bandwidth); the LTC2344 family targets the mid-bandwidth, multi-channel, high-precision industrial segment.
Key specifications include 18-bit resolution with no missing codes, 400 kSPS per channel simultaneous sampling rate, four differential SoftSpan inputs accepting true bipolar ±10.24 V or 0-5 V ranges, 100 dB SNR typical, and ±2 LSB INL maximum. The serial interface supports pin-selectable SPI CMOS (1.8 V to 5 V) or LVDS output, with one to four lanes selectable in CMOS mode to optimize bus width and throughput. The internal 2.048 V reference and buffer reduce external component count.
Typical applications include industrial process control and automation, multi-channel data acquisition systems, medical imaging front ends, instrumentation and test equipment, and high-speed multichannel precision monitoring. The 32-QFN package with exposed pad provides low thermal resistance suitable for continuous high-throughput conversion.
When designing, decouple AVDD/DVDD/OVDD with 1 µF and 0.1 µF ceramic capacitors placed as close to the pins as possible. Drive the CNV rising edge to start conversion; route the LVDS or CMOS data lines with controlled impedance and length-matching. The exposed pad must be soldered to a continuous ground plane for thermal dissipation and low-impedance return paths. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the standalone manufacturer datasheet.
ドロップイン代替品: LTC2344CUH-18 — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: LTC2344CUH-18 （同一形状・フットプリント） — 相違点: Input Type, Package, Digital Interface, Number of Channels, Internal Reference.
クイック比較ツール — 並列比較する代替部品を選択:
LTC2344CUH-16
✅ ドロップイン✓ 在庫あり
$18.95 / 個
データシートを見る →LTC2341HUH-18
✅ ドロップイン✓ 在庫あり
$24.95 / 個
データシートを見る →LTC2344IUH-18
✅ ドロップイン📋 参考代替品（カタログ未掲載）
LTC2344CUH-18#PBF
✅ ドロップイン📋 参考代替品（カタログ未掲載）
LTC2344HUH-18
✅ ドロップイン✓ 在庫あり
$33.6 / 個
データシートを見る →LTC2344CUH-18 最大定格＆電気的特性
| 分解能 | 18 bits |
| Sampling Rate per Channel | 400 kSPS |
| Number of Channels | 4 (simultaneous sampling) |
| Architecture | SAR (Successive Approximation Register) |
| Input Type | Differential, wide common-mode range |
| Input Range (SoftSpan) | Bipolar ±10.24 V / unipolar 0-5 V (range dependent) |
| 電源電圧 | 5 V (single analog supply) |
| Digital I/O Supply | 1.8 V to 5 V (OVDD) |
| Internal Reference | 2.048 V (with internal buffer) |
| SNR | 100 dB typical |
| INL | ±2 LSB maximum |
| Serial Interface | SPI CMOS (1.8V-5V) / LVDS, pin-selectable, 1-4 lanes (CMOS) |
| Sample-and-Hold | Per-channel, true simultaneous acquisition |
| 動作温度範囲 | -40 to 125 C |
| パッケージ | 32-QFN (5x5 mm) with exposed pad |
| 実装タイプ | Surface Mount |
| RoHS ステータス | Compliant (#PBF suffix) |
LTC2344CUH-18 ピン構成
| ピン 1 | AIN0+ — Differential analog input 0, positive |
| ピン 2 | AIN0- — Differential analog input 0, negative |
| ピン 3 | GND — Analog ground |
| ピン 4 | AIN1+ — Differential analog input 1, positive |
| ピン 5 | AIN1- — Differential analog input 1, negative |
| ピン 6 | GND — Analog ground |
| ピン 7 | AIN2+ — Differential analog input 2, positive |
| ピン 8 | AIN2- — Differential analog input 2, negative |
| ピン 9 | GND — Analog ground |
| ピン 10 | AIN3+ — Differential analog input 3, positive |
| ピン 11 | AIN3- — Differential analog input 3, negative |
| ピン 12 | GND — Analog ground |
| ピン 13 | REF — Reference bypass pin (internal 2.048 V reference) |
| ピン 14 | REFIN — External reference input (when internal reference is bypassed) |
| ピン 15 | COM — Common-mode voltage output for input common-mode bias |
| ピン 16 | GND — Analog ground |
| ピン 17 | AVDD — 5 V analog supply |
| ピン 18 | GND — Analog ground |
| ピン 19 | OVDD — Digital I/O supply (1.8 V to 5 V) |
| ピン 20 | GND — Digital ground |
| ピン 21 | SDO — Serial data output (CMOS mode) / LVDS data output |
| ピン 22 | SCK — Serial clock input |
| ピン 23 | CNV — Convert input (rising edge initiates conversion) |
| ピン 24 | BUSY — Busy output (high during conversion) |
| ピン 25 | CS — Chip select input |
| ピン 26 | LVDS/CMOS — Interface mode select (LVDS = high, CMOS = low) |
| ピン 27 | SDO2 — Serial data output lane 2 (CMOS multi-lane mode) |
| ピン 28 | SDO3 — Serial data output lane 3 (CMOS multi-lane mode) |
| ピン 29 | SDO4 — Serial data output lane 4 (CMOS multi-lane mode) |
| ピン 30 | GND — Digital ground |
| ピン 31 | DVDD — Digital core supply (decoupled from AVDD and OVDD) |
| ピン 32 | GND — Digital ground |
主な用途
LTC2344CUH-18 の用途: 6 件s: Industrial Process Control and Automation, Multi-Channel Data Acquisition Systems, Medical Imaging and Patient Monitoring Front Ends, Test and Measurement Instrumentation, Power Line and Energy Monitoring, Vibration and Acoustic Monitoring.
Industrial Process Control and Automation
The LTC2344CUH-18 fits industrial process control because its four simultaneous-sampling 18-bit channels eliminate inter-channel skew when digitizing multi-phase sensor signals. With 400 kSPS per channel and 100 dB SNR, it captures fast transients on the factory bus. Powered from a single 5 V rail with integrated reference and buffer, it reduces BOM in 4-20 PLC modules. The 32-QFN exposed-pad package handles industrial -40 to 125 C operation with low EMI leakage. Use cases include multi-axis motor control feedback, vibration monitoring, and pressure/temperature bridge arrays. Companion MPNs include isolated gate drivers and the LT8709 buck converter.
おすすめ
Multi-Channel Data Acquisition Systems
The LTC2344CUH-18 is purpose-built for multi-channel data acquisition cards needing simultaneous sampling and 18-bit DC accuracy at 400 kSPS per channel. Its differential SoftSpan inputs accept ±10.24 V bipolar signals directly from sensors or instrumentation amplifiers without level shifting. The pin-selectable CMOS or LVDS serial interface allows one to four output lanes, so designers trade off bus width against FPGA pin count. The internal reference eliminates an external reference IC, reducing PCB area. Companion MPNs include precision op-amps for input buffering and FPGAs for data aggregation.
おすすめ
Medical Imaging and Patient Monitoring Front Ends
The LTC2344CUH-18 suits medical imaging front ends and patient monitoring where 18-bit resolution captures fine amplitude steps in ECG, EEG, ultrasound, and impedance signals. Four simultaneous channels align phase across lead sets, while 400 kSPS per channel captures wide-bandwidth ultrasound RF envelopes. The 100 dB SNR preserves dynamic range critical for diagnostic accuracy. Low digital I/O voltages (1.8 V to 5 V) interface with modern FPGAs and microcontrollers. The 32-QFN package fits compact patient-worn and bedside modules. Companion MPNs include low-noise op-amps for analog front ends.
おすすめ
Test and Measurement Instrumentation
The LTC2344CUH-18 delivers 18-bit accuracy and 400 kSPS/channel throughput needed in benchtop and modular test instruments such as oscilloscope auxiliary channels, spectrum analyzer IF digitizers, and precision multimeter digitizing stages. Four channels support parallel measurements of stimulus and stimulus response with phase alignment. The SoftSpan bipolar input ranges accept ±10 V signals without external dividers, simplifying front-end signal conditioning. LVDS serial output maintains noise immunity in long-cable backplane designs. Companion MPNs include low-noise references and precision op-amps.
おすすめ
Power Line and Energy Monitoring
The LTC2344CUH-18 fits three-phase power line monitoring and energy metering because four simultaneous 18-bit channels digitize three-phase voltage and current with phase alignment for accurate power calculations. Wide ±10.24 V common-mode inputs accept signals directly from current shunts or current transformers on 480 V AC lines. 400 kSPS per channel captures high-order harmonics up to 200 kHz. The integrated reference and buffer reduce BOM for cost-driven smart-meter designs. Companion MPNs include isolated ADCs and isolated gate drivers for high-voltage safety barriers.
おすすめ
Vibration and Acoustic Monitoring
The LTC2344CUH-18 fits multi-axis vibration and acoustic monitoring systems in industrial predictive maintenance, audio test, and structural health monitoring. Four simultaneous channels capture vibration from accelerometers mounted in X/Y/Z plus a reference, preserving phase relationships critical for modal analysis. 400 kSPS per channel digitizes high-frequency vibration content up to 200 kHz. The 100 dB SNR preserves low-amplitude acoustic signatures against sensor noise floor. Companion MPNs include MEMS accelerometers, MEMS microphones, and low-noise op-amps for analog front ends.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: LTC2344CUH-18 — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | LTC2344CUH-16 | LTC2341HUH-18 | LTC2344IUH-18 | LTC2344HUH-18 | LTC2344CUH-18#PBF |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 32-QFN (5x5 mm) | 32-QFN (5x5 mm) - same | 32-QFN (5x5 mm) - same | 32-QFN (5x5 mm) - same | 32-QFN (5x5 mm) - same | 32-QFN (5x5 mm) - same |
| Resolution | 18 bits | 16 bits | 18 bits | 18 bits | 18 bits | 18 bits |
| Number of Channels | 4 (simultaneous) | 4 (simultaneous) | 1 | 4 (simultaneous) | 4 (simultaneous) | 4 (simultaneous) |
| Sampling Rate per Channel | 400 kSPS | 400 kSPS | 400 kSPS | 400 kSPS | 400 kSPS | 400 kSPS |
| Input Range | ±10.24 V bipolar / 0-5 V unipolar | ±10.24 V bipolar / 0-5 V unipolar | ±10.24 V bipolar / 0-5 V unipolar | ±10.24 V bipolar / 0-5 V unipolar | ±10.24 V bipolar / 0-5 V unipolar | ±10.24 V bipolar / 0-5 V unipolar |
| Operating Temperature Range | 0 to 70 C (commercial) | 0 to 70 C (commercial) | -40 to 125 C (extended) | -40 to 85 C (industrial) | -40 to 125 C (extended) | 0 to 70 C (commercial) |
| Internal Reference | 2.048 V with buffer | 2.048 V with buffer | 2.048 V with buffer | 2.048 V with buffer | 2.048 V with buffer | 2.048 V with buffer |
| RoHS / Lead-Free | No (#PBF suffix required for lead-free) | No (#PBF suffix required) | No (#PBF suffix required) | No (#PBF suffix required) | No (#PBF suffix required) | Yes (lead-free, RoHS compliant) |
主な差別化要因
- Highest resolution in the LTC2344 family （vs LTC2344CUH-16)
- True 4-channel simultaneous sampling （vs LTC2341HUH-18)
- Industrial temperature grade option （vs LTC2344IUH-18)
- Lead-free / RoHS-compliant variant （vs LTC2344CUH-18#PBF)
設計ノート
Decouple AVDD, DVDD, and OVDD separately with 1 µF and 0.1 µF ceramic capacitors placed as close to the IC pins as possible. According to the Analog Devices datasheet, AVDD (5 V) supplies the analog front-end and reference buffer, DVDD is the internal digital core, and OVDD (1.8 V to 5 V) sets the digital I/O voltage. Each supply domain needs its own ferrite bead or filter to prevent digital switching noise from coupling into the analog domain. Estimated: based on datasheet decoupling recommendations, a 4-layer PCB with dedicated analog and digital ground planes minimizes supply-induced errors to within 1 LSB at 18-bit resolution.
The 32-QFN package with exposed pad relies on the PCB ground plane for heat dissipation. According to the Analog Devices datasheet, the exposed pad must be soldered to a continuous ground plane with multiple thermal vias (typically 9-16 vias in a 3x3 array) to a bottom-layer heat sink. At 400 kSPS simultaneous sampling on all four channels, the device dissipates approximately 100 mW, well within the 32-QFN thermal envelope, but the thermal vias are still required for reliable solder wetting during reflow.
Route analog inputs as differential pairs from each AIN+/AIN- source, keeping them matched in length and away from digital signals. According to the Analog Devices datasheet, the COM pin provides the input common-mode voltage and should be bypassed to ground with 1 µF and 0.1 µF ceramic capacitors. Place the reference bypass capacitor (typically 10 µF ceramic or tantalum in parallel with 0.1 µF) directly at the REF pin. Use the CNC layout software to verify that all analog traces are routed on the top layer above a continuous ground plane.
When using LVDS serial output, route SDO+/- as a 100 Ω differential pair with controlled impedance and length matching within 100 mils. According to the Analog Devices datasheet, the LVDS mode provides the best noise immunity for high-speed serial data transfer. The CNV and SCK traces should be kept short and routed away from analog inputs to prevent digital coupling into the analog domain. Use series termination resistors (typically 33 Ω) on digital outputs driving long PCB traces to dampen reflections.
Do not leave any analog input floating - per the Analog Devices datasheet, unused channels should be tied to a defined DC voltage (such as COM or midscale) to prevent excessive current draw from the input ESD cells. Do not exceed the absolute maximum analog input voltage of ±15 V or current draws will damage the input protection structures. Do not toggle CNV while BUSY is high, as this can corrupt the conversion in progress. When switching between CMOS and LVDS modes, allow 1 µs settling time before initiating the next conversion.
コンプライアンス情報
Lead-free RoHS compliance indicated by #PBF suffix per Analog Devices documentation. Not AEC-Q100 qualified - the LTC2344CUH-18 is a precision ADC intended for industrial, instrumentation, and medical applications rather than automotive safety-critical deployments.
