LTC2270IUP - 16-Bit 20Msps Dual ADC, 84.1dB SNR | Analog Devices
MPN: LTC2270IUP ✓ Hoạt độngLTC2270IUP Tóm tắt
An ADC (analog-to-digital converter) is a mixed-signal integrated circuit that quantifies continuous-time analog voltages into discrete digital codes, forming the bridge between the analog front end (sensors, filters, amplifiers) and the digital signal processor or FPGA. In the system hierarchy, the LTC2270IUP sits between the analog conditioning stage and the digital processor: signal chain -> data acquisition -> ADC -> DSP/FPGA. Pipelined ADCs like the LTC2270 use a multi-stage architecture to achieve high sampling rates (tens of Msps) while preserving 14-16 bit resolution, and dual-channel simultaneous sampling means both channels share the same encode clock edge - critical for I/Q demodulation and phase-coherent measurements.
Key features of the LTC2270IUP include 84.1 dB SNR, 99 dB SFDR, 2-channel simultaneous sampling at 20 Msps per channel, and an industrial temperature range of -40C to +85C. The 64-lead QFN (9x9 mm) package exposes a thermal pad for low thermal resistance, while differential inputs reject common-mode noise. The pipelined architecture provides low latency relative to sigma-delta ADCs of equivalent bandwidth.
The LTC2270 is fabricated on a BiCMOS process optimized for high-speed sampling, supporting single 3V analog supply and 1.8V-3V digital supply. Internal reference and selectable input ranges simplify board design, while the LVDS or CMOS digital output interface (variant-dependent) integrates with FPGAs and ASICs. Optional dithering mode can be enabled to improve SFDR for small-signal or single-tone input scenarios.
Typical applications include communications receivers (cellular base stations, software-defined radio), medical imaging (ultrasound beamformers), high-end instrumentation, and multi-channel data acquisition systems. The 84.1 dB SNR and 99 dB SFDR make it well suited to wide dynamic range signals.
When designing with this part, pay close attention to analog input common-mode voltage and the driven front-end amplifier selection. The encode clock jitter directly limits SNR at high input frequencies - a low-jitter clock source is essential to preserve the datasheet's AC performance.
This page synthesizes distributor pricing, drop-in alternatives from the LTC2208/LTC226x family, and practical design notes not consolidated in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho LTC2270IUP — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với LTC2270IUP (cùng hình factor và footprint) — khác nhau ở Number of Channels, Package, RoHS Status, Input Type, Resolution.
LTC2270IUP#TRPBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC2270IUP#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC2208IUP#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC2155CUP-12
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →LTC2184IUP
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →LTC2241IUP-12
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →LTC2270IUP Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 16 bit |
| Number of Channels | 2 (simultaneous sampling) |
| Tỷ lệ lấy mẫu | 20 Msps per channel |
| Architecture | Pipelined |
| Signal-to-Noise Ratio (SNR) | 84.1 dB |
| Spurious-Free Dynamic Range (SFDR) | 99 dB |
| Input Type | Differential |
| Analog Supply Voltage | 3.0 V (typical) |
| Digital Supply Voltage | 1.8 V to 3.0 V |
| Khoảng nhiệt độ hoạt động | -40C to +85C (industrial grade, I-suffix) |
| Hộp | 64-pin QFN (9x9 mm), exposed pad |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant (PBF suffix) |
| Lead-Free | Yes |
Cấu hình chân LTC2270IUP
| Chân 1 | GND — Ground |
| Chân 2 | GND — Ground |
| Chân 3 | VA — Analog 3V supply |
| Chân 4 | VREF — Voltage reference |
| Chân 5 | GND — Ground |
| Chân 6 | AIN1+ — Channel 1 positive analog input |
| Chân 7 | AIN1- — Channel 1 negative analog input |
| Chân 8 | GND — Ground |
| Chân 9 | AIN2+ — Channel 2 positive analog input |
| Chân 10 | AIN2- — Channel 2 negative analog input |
| Chân 11 | GND — Ground |
| Chân 12 | VA — Analog 3V supply |
| Chân 13 | GND — Ground |
| Chân 14 | GND — Ground |
| Chân 15 | ENC+ — Encode clock positive input |
| Chân 16 | ENC- — Encode clock negative input |
| Chân 17 | GND — Ground |
| Chân 18 | DITH — Dither enable |
| Chân 19 | SHDN — Shutdown (active high) |
| Chân 20 | GND — Ground |
| Chân 21 | VD — Digital 1.8-3V supply |
| Chân 22 | GND — Ground |
| Chân 23 | D1A0 — Channel 1 data output bit 0 (LSB) |
| Chân 24 | D1A1 — Channel 1 data output bit 1 |
| Chân 25 | D1A2 — Channel 1 data output bit 2 |
| Chân 26 | D1A3 — Channel 1 data output bit 3 |
| Chân 27 | D1A4 — Channel 1 data output bit 4 |
| Chân 28 | D1A5 — Channel 1 data output bit 5 |
| Chân 29 | D1A6 — Channel 1 data output bit 6 |
| Chân 30 | D1A7 — Channel 1 data output bit 7 |
| Chân 31 | D1A8 — Channel 1 data output bit 8 |
| Chân 32 | D1A9 — Channel 1 data output bit 9 |
| Chân 33 | D1A10 — Channel 1 data output bit 10 |
| Chân 34 | D1A11 — Channel 1 data output bit 11 |
| Chân 35 | D1A12 — Channel 1 data output bit 12 |
| Chân 36 | D1A13 — Channel 1 data output bit 13 |
| Chân 37 | D1A14 — Channel 1 data output bit 14 |
| Chân 38 | D1A15 — Channel 1 data output bit 15 (MSB) |
| Chân 39 | D1OR — Channel 1 out-of-range indicator |
| Chân 40 | GND — Ground |
| Chân 41 | VD — Digital 1.8-3V supply |
| Chân 42 | D2A0 — Channel 2 data output bit 0 (LSB) |
| Chân 43 | D2A1 — Channel 2 data output bit 1 |
| Chân 44 | D2A2 — Channel 2 data output bit 2 |
| Chân 45 | D2A3 — Channel 2 data output bit 3 |
| Chân 46 | D2A4 — Channel 2 data output bit 4 |
| Chân 47 | D2A5 — Channel 2 data output bit 5 |
| Chân 48 | D2A6 — Channel 2 data output bit 6 |
| Chân 49 | D2A7 — Channel 2 data output bit 7 |
| Chân 50 | D2A8 — Channel 2 data output bit 8 |
| Chân 51 | D2A9 — Channel 2 data output bit 9 |
| Chân 52 | D2A10 — Channel 2 data output bit 10 |
| Chân 53 | D2A11 — Channel 2 data output bit 11 |
| Chân 54 | D2A12 — Channel 2 data output bit 12 |
| Chân 55 | D2A13 — Channel 2 data output bit 13 |
| Chân 56 | D2A14 — Channel 2 data output bit 14 |
| Chân 57 | D2A15 — Channel 2 data output bit 15 (MSB) |
| Chân 58 | D2OR — Channel 2 out-of-range indicator |
| Chân 59 | GND — Ground |
| Chân 60 | VD — Digital 1.8-3V supply |
| Chân 61 | GND — Ground |
| Chân 62 | GND — Ground |
| Chân 63 | VA — Analog 3V supply |
| Chân 64 | GND — Ground |
Ứng dụng tiêu biểu
LTC2270IUP phù hợp cho 6 Áp dụngs: Cellular Base Station Receiver, Medical Ultrasound Beamforming, Software Defined Radio (SDR), Multi-Channel Data Acquisition System, Instrumentation and Test Equipment, Radar and Phased-Array Front Ends.
Cellular Base Station Receiver
The LTC2270IUP's dual simultaneous-sampling 16-bit 20 Msps channels directly digitize the I and Q baseband outputs of a cellular base-station receiver, preserving phase coherence between the two channels. Its 84.1 dB SNR gives a 14+ ENOB dynamic range, allowing the receiver to detect small signals alongside large interferers without saturating, while 99 dB SFDR keeps intermodulation spurs below the noise floor of the demodulation chain. Power consumption is moderate thanks to a 3V analog supply, simplifying thermal design in densely populated BTS shelves. The 64-QFN package exposes a thermal pad that bonds to the ground plane, removing the need for a heatsink at typical base-station baseband sample rates.
Được đề xuất
Medical Ultrasound Beamforming
Ultrasound beamformers require many simultaneously sampled channels with high SNR to detect weak returning echoes. The LTC2270IUP provides two such channels per chip with 84.1 dB SNR and 99 dB SFDR, allowing 14+ effective bits to be preserved across the dynamic range of tissue echoes. At 20 Msps per channel, the ADC comfortably digitizes up to 10 MHz of transducer bandwidth after anti-alias filtering. The 64-QFN 9x9 mm footprint is small enough to permit high channel density on the beamformer PCB, while the industrial -40C to +85C temperature grade supports the operating environment of cart-based and portable ultrasound systems. Designers should pair this ADC with a low-noise LNA such as the AD8021 to fully realize the 84 dB SNR.
Được đề xuất
Software Defined Radio (SDR)
Software-defined radios need wide dynamic range ADCs to capture both strong and weak signals without front-end filtering. The LTC2270IUP's 84.1 dB SNR and 99 dB SFDR give SDR platforms a wide spurious-free window, while 20 Msps per channel is sufficient to digitize intermediate-frequency (IF) signals of several MHz bandwidth on two independent paths. Industrial temperature grade and small 64-QFN footprint suit portable SDR equipment and laboratory bench instruments. The encode clock must be sourced from a low-phase-noise TCXO or PLL; jitter above 1 ps RMS will degrade SNR noticeably at high IF frequencies. Pairing this ADC with a wideband LNA/ mixer front end and an FPGA-based digital downconverter yields a flexible SDR platform.
Được đề xuất
Multi-Channel Data Acquisition System
Multi-channel data acquisition cards digitize analog signals from sensors, filters, and process-control transducers. The LTC2270IUP provides two simultaneously sampled 16-bit channels per chip, allowing high channel-count DAQ boards to scale efficiently by stacking devices. Its 84.1 dB SNR suits precision DC and low-frequency AC measurements, and the 64-QFN package fits standard DAQ card form factors. The 3V analog supply simplifies power tree design. A typical DAQ front end uses an instrumentation amplifier (e.g., AD8253) followed by an anti-alias filter and the LTC2270IUP, with the digital outputs captured by an FPGA and forwarded over PCIe to the host processor.
Được đề xuất
Instrumentation and Test Equipment
Test and measurement instruments such as oscilloscopes, spectrum analyzers, and arbitrary waveform generators depend on high-SNR ADCs. The LTC2270IUP's 84.1 dB SNR and 99 dB SFDR deliver the linearity required to characterize 16-bit DACs and precision analog signals. Dual simultaneous sampling lets the instrument capture a stimulus and response on a single clock edge, which is critical for stimulus-response testing. The 64-QFN industrial-grade package supports the extended operating environments of laboratory and production-floor equipment. For best AC performance, designers should follow the datasheet's recommended analog-input drive circuit and use a low-jitter clock generator such as the AD9516.
Được đề xuất
Radar and Phased-Array Front Ends
Phased-array radar systems require many simultaneously sampled channels with matched gain and phase characteristics. The LTC2270IUP's two channels per package sample on the same encode edge, eliminating channel-to-channel skew. Its 84.1 dB SNR preserves target detection range while 99 dB SFDR avoids false targets from intermodulation spurs. The 20 Msps rate is well matched to IF frequencies used in ground-based surveillance and weather radar. Multiple LTC2270IUP devices can be arrayed with shared low-jitter clocks and identical analog front ends to build large coherent receive arrays. Industrial temperature grade supports outdoor and military-environment deployment.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho LTC2270IUP — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | LTC2270IUP#TRPBF | LTC2270IUP#PBF | LTC2208IUP#PBF | LTC2155CUP-12 | LTC2184IUP |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 64-QFN (9x9) | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same |
| Resolution | 16 bit | 16 bit | 16 bit | 16 bit | 12 bit | 16 bit |
| Number of Channels | 2 (simultaneous) | 2 | 2 | 1 | 2 | 2 |
| Sampling Rate | 20 Msps | 20 Msps | 20 Msps | 40 Msps | 170 Msps | 105 Msps |
| Operating Temperature | -40C to +85C (I-suffix) | -40C to +85C | -40C to +85C | -40C to +85C | 0C to +70C (C-suffix) | -40C to +85C |
Bảo phân biệt quan trọng
- Dual simultaneous sampling at 16-bit 20 Msps (vsLTC2208IUP#PBF)
- Higher SNR/SFDR at moderate sample rates (vsLTC2155CUP-12)
- Industrial temperature grade in standard pinout (vsLTC2155CUP-12)
Ghi chú thiết kế
Clock jitter directly degrades ADC SNR. The LTC2270IUP's 84.1 dB SNR assumes an encode clock with jitter below approximately 1 ps RMS. Using a general-purpose FPGA clock output or a noisy PLL will visibly reduce SNR, especially at high input frequencies. Use a dedicated low-jitter clock generator such as the AD9516 or a clean TCXO, and place clock traces away from switching signals.
Differential analog inputs must be routed as a matched pair with 100 ohm differential impedance on the PCB. Use a balanced transformer (e.g., ADT1-1WT) or a fully differential driver amplifier (e.g., AD8138) to convert the single-ended signal source to differential. Route the analog inputs symmetrically, with the two traces the same length and surrounded by continuous ground. Keep digital output traces away from the analog input pins to avoid digital-noise coupling.
The 64-QFN exposed pad is the primary thermal path; it MUST be soldered to a continuous ground plane with multiple thermal vias. Estimated: at 3V analog supply and full 20 Msps operation, the die dissipates roughly 200-300 mW, which is well within the package's thermal budget, but only if the EP is properly soldered. Decouple each VA and VD pin with a 0.1 uF X7R capacitor placed as close as possible to the pin, and add a 10 uF bulk capacitor near the analog supply input.
The LTC2270IUP CMOS parallel outputs drive significant current at 20 Msps, with each output toggling at 20 MHz. Add 33 ohm series damping resistors near the ADC outputs to reduce ringing into the FPGA receiver. Place the ADC and FPGA on the same side of the PCB or use matched-length microstrip, and provide a clean 1.8-3V digital supply. For the highest data-integrity margins, consider the LVDS output variant of the LTC22xx family instead of the CMOS version.
Thông tin tuân thủ
RoHS compliant per #PBF suffix. Industrial temperature grade (I-suffix) only; AEC-Q100 automotive grade not offered in this family.
