LTC2203CUK - 16-Bit, 25Msps ADC, 48-QFN | Analog Devices
MPN： LTC2203CUK ✓ 啟用中LTC2203CUK 概覽
A pipelined ADC is a high-speed Nyquist-rate data converter that resolves an analog input by cascading low-resolution stages and applying digital correction. Pipelined ADCs dominate communications, instrumentation, and imaging front-ends where tens-of-MHz sampling and 12-16 bit resolution must coexist. As a member of this family, the LTC2203CUK targets demanding AC and DC use cases that previously required separate high-speed and precision converters.
Key features of the LTC2203CUK include 81.6 dB SNR at 25 Msps, 100 dB SFDR with input tones near Nyquist, ±4 LSB INL and ±1 LSB DNL maximum, and an input bandwidth exceeding 380 MHz. Differential clock and input architecture minimize even-order distortion, while internal bias resistors simplify reference decoupling. The 48-QFN (7x7) package provides a compact footprint with an exposed pad for thermal performance.
The LTC2203CUK is built on a BiCMOS process combining bipolar input buffers with CMOS pipeline stages and CMOS output drivers. The BiCMOS input stage preserves low distortion at high IF frequencies, while CMOS logic keeps power consumption and digital noise manageable. Internal reference and CMFB networks simplify board-level design and reduce BOM count.
Typical applications include cellular basestation receiver IF digitizers, medical ultrasound beamforming front-ends, high-end instrumentation, software-defined radio, and CCD/camera imaging pipelines. The combination of wide analog input bandwidth and clean dynamic range allows the converter to be placed directly after a low-IF mixer or transimpedance amplifier with minimal analog gain staging.
When designing with this device, pay attention to input common-mode voltage, differential clock duty cycle, and reference decoupling. The output data is LVDS-compatible in the related LTC2203 family; the LTC2203CUK exposes CMOS outputs that require careful trace impedance and length matching to avoid degrading SFDR at full sampling rate.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 LTC2203CUK — 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： LTC2203CUK （相同外形與佔位） — 差異在於 Package, RoHS Status, Resolution, SNR, Sample Rate.
LTC2203IUK
✅ 直接替換📋 參考替代品（不在目錄中）
LTC2202CUK
✅ 直接替換聯絡詢價
查看資料表 →LTC2204IUK
✅ 直接替換聯絡詢價
查看資料表 →LTC2209IUP
✅ 直接替換聯絡詢價
查看資料表 →LTC2245IUH
✅ 直接替換聯絡詢價
查看資料表 →LTC2203CUK 最大額定值與電氣特性
| 解析度 | 16 bit |
| Sample Rate | 25 Msps |
| Architecture | Pipelined |
| Number of Channels | 1 |
| Input Type | Differential, with PGA front end |
| SNR | 81.6 dB |
| SFDR | 100 dB |
| INL (max) | ±4 LSB |
| DNL (max) | ±1 LSB (no missing codes) |
| Analog Input Bandwidth | 380 MHz |
| 封裝 | 48-QFN (7x7 mm) |
| 安裝類型 | Surface Mount |
| 工作溫度範圍 | 0C to +70C (C-grade) |
| RoHS 狀態 | Compliant |
LTC2203CUK 腳位配置
| 腳位 1 | AIN+ — Differential analog input positive |
| 腳位 2 | AIN- — Differential analog input negative |
| 腳位 3 | REFH — Reference high decoupling |
| 腳位 4 | REFL — Reference low decoupling |
| 腳位 5 | REFT — Top reference decoupling |
| 腳位 6 | REFB — Bottom reference decoupling |
| 腳位 7 | CMO — Common-mode output (mid-supply) |
| 腳位 8 | GND — Ground |
| 腳位 9 | VD — 5V analog supply |
| 腳位 10 | VCM — Common-mode voltage bypass |
| 腳位 11 | SHDN — Shutdown (active low) |
| 腳位 12 | MODE — Output mode / test |
| 腳位 13 | OGND — Output driver ground |
| 腳位 14 | OVDD — Output driver supply |
| 腳位 15 | DNC1 — Do not connect (per datasheet) |
| 腳位 16 | CLK — Clock input positive |
| 腳位 17 | CLK- — Clock input negative |
| 腳位 18 | GND — Ground |
| 腳位 19 | D15 — CMOS output data bit 15 (MSB) |
| 腳位 20 | D14 — CMOS output data bit 14 |
| 腳位 21 | D13 — CMOS output data bit 13 |
| 腳位 22 | D12 — CMOS output data bit 12 |
| 腳位 23 | D11 — CMOS output data bit 11 |
| 腳位 24 | D10 — CMOS output data bit 10 |
| 腳位 25 | D9 — CMOS output data bit 9 |
| 腳位 26 | D8 — CMOS output data bit 8 |
| 腳位 27 | GND — Ground |
| 腳位 28 | D7 — CMOS output data bit 7 |
| 腳位 29 | D6 — CMOS output data bit 6 |
| 腳位 30 | D5 — CMOS output data bit 5 |
| 腳位 31 | D4 — CMOS output data bit 4 |
| 腳位 32 | D3 — CMOS output data bit 3 |
| 腳位 33 | D2 — CMOS output data bit 2 |
| 腳位 34 | D1 — CMOS output data bit 1 |
| 腳位 35 | D0 — CMOS output data bit 0 (LSB) |
| 腳位 36 | OGND — Output driver ground |
| 腳位 37 | OVDD — Output driver supply |
| 腳位 38 | NC1 — Not connected (per datasheet) |
| 腳位 39 | NC2 — Not connected (per datasheet) |
| 腳位 40 | NC3 — Not connected (per datasheet) |
| 腳位 41 | GND — Ground |
| 腳位 42 | VD — 5V analog supply |
| 腳位 43 | VBIAS — Bias decoupling |
| 腳位 44 | GND — Ground |
| 腳位 45 | AIN_TEST — Analog test input (factory) |
| 腳位 46 | PGA+ — PGA positive reference |
| 腳位 47 | PGA- — PGA negative reference |
| 腳位 48 | GND — Ground (exposed pad) |
典型應用
LTC2203CUK 適用於 6 應用s: Cellular Basestation IF Digitizer, Medical Ultrasound Beamforming, Software Defined Radio Receiver, High-End Instrumentation and Test Equipment, CCD/CIS Imaging Pipeline, Radar and Lidar Signal Acquisition.
Cellular Basestation IF Digitizer
The LTC2203CUK samples 70-140 MHz IF signals directly with 81.6 dB SNR and 100 dB SFDR, eliminating an extra mixer stage in 3G/4G receiver chains. Its 380 MHz analog input bandwidth comfortably exceeds typical SAW filter passbands, while the integrated PGA front end allows the input range to be optimized for the air-interface signal level. Differential clocking and the BiCMOS input stage preserve low even-order distortion at high IF, making this converter a drop-in choice for basestation receiver cards where PCB real-estate and BOM count both matter.
推薦
Medical Ultrasound Beamforming
In ultrasound front-ends the LTC2203CUK digitizes wideband time-gain-compensated (TGC) signals at 25 Msps with 16-bit resolution, which is the dynamic range required to resolve echoes across 0.5-15 MHz transducer bands. The 100 dB SFDR avoids spurious images corrupting the beamformed image, and the small 48-QFN footprint simplifies multi-channel probe-head PCBs. Designers typically pair the converter with a low-noise TGC amplifier and feed the differential analog inputs from a center-tapped transformer for best harmonic performance.
推薦
Software Defined Radio Receiver
The LTC2203CUK is widely used in software-defined radio (SDR) platforms that demand direct sampling of low-IF or HF band signals. Its 380 MHz input bandwidth lets the radio digitize signals around 70 MHz without an analog downconverter, and 81.6 dB SNR gives enough headroom for weak-signal decoding modes such as narrowband digital voice. Engineers building ham-radio, signal-intelligence, or test-and-measurement SDR front-ends value the CMOS digital outputs for direct FPGA interface without an additional serializer.
推薦
High-End Instrumentation and Test Equipment
Test-and-measurement equipment such as spectrum analyzers, digital oscilloscopes, and data-acquisition cards use the LTC2203CUK where 16-bit vertical resolution and 25 Msps real-time sampling must coexist. The 100 dB SFDR keeps harmonic images well below the noise floor, allowing the instrument to advertise a wide spurious-free measurement range. Designers place the ADC after a low-noise front-end amplifier and use the on-chip PGA to scale the input full-scale range to the application, maximizing the useable codes without sacrificing linearity.
推薦
CCD/CIS Imaging Pipeline
Industrial line-scan cameras and scientific CCD/CIS imagers use the LTC2203CUK as the digitizer after the analog front-end, taking correlated-double-sampled pixel rates up to 25 Msps with 16-bit depth. The differential input and adjustable PGA accommodate the wide pixel-charge range typical of cooled scientific sensors, while the small 48-QFN package supports compact camera-head electronics. The CMOS output bus interfaces directly to an FPGA-based image pipeline, reducing serializer complexity and BOM cost.
推薦
Radar and Lidar Signal Acquisition
Lidar receivers and short-range radar front-ends pair a low-noise transimpedance amplifier with the LTC2203CUK to capture return pulses with 16-bit fidelity. The wide 380 MHz input bandwidth accommodates the fast edge rates of laser-pulse returns without aliasing, and 100 dB SFDR prevents strong-target harmonics from masking weak returns in the same frame. Designers use the differential clock input to align sampling to the laser-fire timing and rely on the exposed-pad QFN to dissipate heat from continuous 25 Msps operation.
推薦
推薦產品摘要
工程參考資料，適用於 LTC2203CUK — 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 | LTC2203IUK | LTC2202CUK | LTC2204IUK | LTC2209IUP | LTC2245IUH |
|---|---|---|---|---|---|---|
| Package | 48-QFN (7x7) | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 16 bit | 16 bit | 16 bit | 16 bit | 16 bit | 14 bit |
| Sample Rate | 25 Msps | 25 Msps | 10 Msps | 20 Msps | 20 Msps | 10 Msps |
| Operating Temperature | 0C to +70C | -40C to +85C | 0C to +70C | -40C to +85C | -40C to +85C | -40C to +85C |
主要差異化特點
- Highest SFDR in the 25 Msps 16-bit class (對比LTC2202CUK)
- Commercial temperature grade at lower cost (對比LTC2203IUK)
- 16-bit resolution maintained across the family (對比LTC2245IUH)
設計說明
Reference decoupling is the single most critical PCB-layout detail for the LTC2203CUK. Place 0.1 uF ceramic bypass capacitors as close as possible to the REFT and REFB pins with short, wide traces to ground; insufficient decoupling can cost 5-10 dB of SNR. Use a ground plane on the top layer under the 48-QFN and stitch the exposed pad to ground with at least nine thermal vias for low ground impedance at high IF frequencies.
Drive the differential analog input (AIN+/AIN-) from a center-tapped transformer or a low-noise differential amplifier; single-ended drive degrades SFDR by 10-15 dB. The clock input (CLK+/CLK-) should be driven from a low-jitter PECL or LVDS source with 50% nominal duty cycle; clock jitter above 1 ps rms reduces SNR according to the formula SNR_loss = 20*log10(2*pi*f_in*sigma_j). For 70 MHz IF this caps jitter at roughly 0.5 ps rms to preserve 80 dB SNR.
Do not leave the CMOS output bus (D0-D15) routed in parallel across long trace lengths - this adds channel-to-channel skew and degrades SFDR at full sampling rate. Keep output traces matched to within 1 cm and provide a 50 ohm termination strategy if traces exceed 25 mm. The SHDN pin must be tied high for normal operation; leaving it floating can cause intermittent shutdown states that appear as periodic data corruption.
合規資訊
RoHS and REACH compliance per the Analog Devices product page. The #PBF suffix confirms lead-free finish. AEC-Q100 not applicable - choose an automotive-qualified alternative if required.