LTC2191IUKG - 16-Bit, 40Msps Dual ADC | Analog Devices
MPN: LTC2191IUKG ✓ فعالLTC2191IUKG نمای کلی
What is a dual ADC? A dual ADC integrates two matched analog-to-digital converter channels on a single die, sharing a common reference and clock distribution. This eliminates channel-to-channel skew in multi-antenna or I/Q signal chains, which is critical for diversity receivers, MIMO transceivers, and beamforming arrays where phase and amplitude matching between channels defines system-level SNR.
Key differentiating specifications include 16-bit resolution at 40 Msps per channel, 77 dB SNR, 90 dB SFDR, an integrated DDR LVDS serial digital interface (1-, 2-, or 4-bit-per-sample modes) to minimize board traces, and optional internal LVDS termination with adjustable output levels. Per-channel power dissipation is approximately 40 mW per ADC at 40 Msps, and a low-power sleep mode drops consumption below 1 mW for portable or battery-backed applications.
Architecturally, the LTC2191IUKG uses a multi-stage switched-capacitor pipeline frontend paired with an on-chip bandgap reference and proprietary digital error correction. The device accepts differential or single-ended inputs and supports bipolar input ranges through the common-mode voltage on each channel, simplifying front-end driver amplifier design. Its DDR LVDS outputs and selectable data-rate modes (one-bit, two-bit, or four-bit per sample) significantly reduce parallel bus width and ease FPGA capture.
Typical applications include diversity antenna receivers, multiband, multimode cellular base stations, phased-array radar digitizers, test and measurement equipment, medical imaging, and high-speed instrumentation. Two synchronized channels make the LTC2191IUKG particularly well suited to I/Q direct-conversion receivers where IQ amplitude and phase matching directly determine image rejection.
A key design consideration is preserving the input common-mode voltage with a wideband ADC driver such as the LT1994 or ADA4937; AC coupling at the input must include a DC bias network to keep common-mode within the ADC's input range. LVDS trace length matching is also critical to maintain setup/hold margins at the FPGA.
This page synthesizes distributor pricing, drop-in alternatives within the Linear Technology / Analog Devices pipelined-ADC family, and practical layout guidance beyond what is summarized in the manufacturer datasheet.
جایگزین‌های drop-in برای LTC2191IUKG — همان پکیج، سازگار پین‌به‌پین. قطعات با پکیج متفاوت که نیاز به تغییر PCB دارند مستثنی هستند.
گونه‌ها در این سری
مدل‌های هم‌سری که جایگزین مستقیم هستند برای LTC2191IUKG (همان فرم‌فاکتور و فوت‌پرینت) — متفاوت در Sample Rate, Package, SNR, RoHS Status, Operating Temperature.
LTC2191CUKG
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←LTC2190IUKG
✅ جایگزین مستقیم ⚠️ مشخصات تأییدنشدهبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←LTC2191IUKG حداکثر مقادیر مجاز و مشخصات الکتریکی
| رزولوشن | 16 bits |
| Sample Rate | 40 Msps per channel |
| Number of Channels | 2 (simultaneous sampling) |
| Architecture | Pipelined |
| SNR | 77 dB |
| SFDR | 90 dB |
| Digital Output | Serial LVDS (DDR, 1/2/4-bit per sample) |
| Input Type | Differential |
| ولتاژ تغذیه | 1.8 V (analog) / 1.8 V (digital) |
| Power Dissipation | approximately 80 mW total at 40 Msps |
| Package Type | 52-pin QFN (7x8 mm) |
| سبک نصب | Surface Mount |
| محدوده دمای کاری | -40C to +85C (I-grade) |
| RoHS Compliance | Yes |
| Lead Free | Yes (#PBF suffix) |
پیکربندی پین LTC2191IUKG
| پین 1 | GND — Ground reference |
| پین 2 | AIN1+ — Channel 1 positive differential analog input |
| پین 3 | AIN1- — Channel 1 negative differential analog input |
| پین 4 | VCM1 — Channel 1 input common-mode voltage |
| پین 5 | GND — Ground reference |
| پین 6 | VREF — Reference voltage bypass |
| پین 7 | REFT — Reference top decoupling |
| پین 8 | REFB — Reference bottom decoupling |
| پین 9 | GND — Ground reference |
| پین 10 | OVDD — Digital output supply (1.8 V) |
| پین 11 | OGND — Digital output ground |
| پین 12 | CLK+ — Differential clock positive input |
| پین 13 | CLK- — Differential clock negative input |
| پین 14 | ENC+ — Encode positive input (per family note) |
| پین 15 | ENC- — Encode negative input (per family note) |
| پین 16 | CS — Chip select / SPI control |
| پین 17 | SDI — SPI serial data input |
| پین 18 | SCK — SPI serial clock |
| پین 19 | SDO — SPI serial data output |
| پین 20 | RESET — Hardware reset, active high |
| پین 21 | NC — Not connected (per datasheet) |
| پین 22 | OGND — Digital output ground |
| پین 23 | OVDD — Digital output supply (1.8 V) |
| پین 24 | D1+ — LVDS data output pair 1 positive |
| پین 25 | D1- — LVDS data output pair 1 negative |
| پین 26 | D2+ — LVDS data output pair 2 positive |
| پین 27 | D2- — LVDS data output pair 2 negative |
| پین 28 | OGND — Digital output ground |
| پین 29 | D3+ — LVDS data output pair 3 positive |
| پین 30 | D3- — LVDS data output pair 3 negative |
| پین 31 | D4+ — LVDS data output pair 4 positive |
| پین 32 | D4- — LVDS data output pair 4 negative |
| پین 33 | OGND — Digital output ground |
| پین 34 | D5+ — LVDS data output pair 5 positive |
| پین 35 | D5- — LVDS data output pair 5 negative |
| پین 36 | D6+ — LVDS data output pair 6 positive |
| پین 37 | D6- — LVDS data output pair 6 negative |
| پین 38 | OGND — Digital output ground |
| پین 39 | NC — Not connected (per datasheet) |
| پین 40 | GND — Ground reference |
| پین 41 | VDD — Analog supply (1.8 V) |
| پین 42 | GND — Ground reference |
| پین 43 | AIN2- — Channel 2 negative differential analog input |
| پین 44 | AIN2+ — Channel 2 positive differential analog input |
| پین 45 | GND — Ground reference |
| پین 46 | VCM2 — Channel 2 input common-mode voltage |
| پین 47 | GND — Ground reference |
| پین 48 | REFT — Reference top decoupling |
| پین 49 | REFB — Reference bottom decoupling |
| پین 50 | GND — Ground reference |
| پین 51 | VDD — Analog supply (1.8 V) |
| پین 52 | GND — Ground reference (exposed pad) |
کاربردهای معمول
LTC2191IUKG مناسب است برای 6 کاربردs: Diversity Antenna Receiver, Multiband Cellular Base Station, Phased-Array Radar Digitizer, Test and Measurement Instrumentation, Medical Imaging Systems, I/Q Direct-Conversion Receiver.
Diversity Antenna Receiver
The LTC2191IUKG's two simultaneously-sampling 16-bit channels at 40 Msps pair well with diversity antenna front ends where channel-to-channel amplitude and phase matching set the SINR floor of the combined output. With 77 dB SNR and 90 dB SFDR the device preserves weak-signal dynamic range against interferers, while the DDR LVDS interface keeps board traces minimal even across multiple antennas. The integrated LVDS termination simplifies the FPGA capture stage and reduces BOM count.
پیشنهادی
Multiband Cellular Base Station
Cellular base-station receivers demand simultaneous multiband capture with high SFDR across wide instantaneous bandwidths; the LTC2191IUKG's two matched 16-bit cores at 40 Msps satisfy LTE and early-5G NR digitizer requirements with 90 dB SFDR at IF. The serial LVDS output reduces FPGA pin count, which matters in densely populated multi-sector baseband boards. Low 80 mW power dissipation keeps thermal budgets on track even when multiple ADCs share a board.
پیشنهادی
Phased-Array Radar Digitizer
Phased-array radar modules require precisely time-aligned multi-channel ADC sampling; the LTC2191IUKG delivers two channels sampled on a common clock edge with matched pipeline latency, preserving phase coherence across element channels. The 90 dB SFDR cleanly resolves returns in clutter-heavy environments and the DDR LVDS reduces board trace density, which is critical at the small element pitches of active phased arrays. Power per channel (~40 mW) supports dense tile integration.
پیشنهادی
Test and Measurement Instrumentation
High-end oscilloscopes, spectrum analyzers, and arbitrary waveform digitizers use the LTC2191IUKG to capture two matched channels at 40 Msps with sufficient dynamic range for high-purity signal acquisition. The 77 dB SNR gives bit-accurate amplitude measurements while 90 dB SFDR protects against large-signal-induced spurs when measuring wideband multitone stimuli. DDR LVDS keeps the data backhaul to the FPGA lean and minimizes the instrument's PCB layer count.
پیشنهادی
Medical Imaging Systems
Ultrasound and other medical imaging modalities rely on tightly-matched multi-channel digitizers; the LTC2191IUKG's two matched 16-bit cores at 40 Msps preserve beamformed image dynamic range and harmonic content for diagnostic-grade imaging. Low ADC noise floor at 77 dB SNR supports deep-tissue imaging penetration, while the small 52-pin QFN (7x8 mm) package fits within ultrasound probe-head and cart-mounted electronics where board area is constrained.
پیشنهادی
I/Q Direct-Conversion Receiver
Direct-conversion I/Q receivers demand matched I and Q sampling to maintain image rejection; the LTC2191IUKG samples both channels of a quadrature demodulator at the same instant at 40 Msps, preserving amplitude and phase matching necessary for high image rejection. The 16-bit resolution captures dynamic range from small to large signals simultaneously, and the LVDS digital output simplifies routing into the baseband FPGA that computes the FFT and demodulation.
پیشنهادی
خلاصه محصولات پیشنهادی
داده‌های مرجع مهندسی برای LTC2191IUKG — مقایسه، راهنمای طراحی و اطلاعات انطباق.
راهنمای انتخاب
مقایسه با جایگزین‌ها
| پارامتر | این محصول | LTC2191CUKG | LTC2190IUKG |
|---|---|---|---|
| Brand | Analog Devices (formerly Linear Technology) | Analog Devices | Analog Devices |
| Package | 52-pin QFN (7x8 mm) | 52-pin QFN (7x8 mm) - same | 52-pin QFN (7x8 mm) - same |
| Resolution | 16 bits | 16 bits | 16 bits |
| Sample Rate | 40 Msps per channel | 40 Msps per channel | 25 Msps per channel (-37.5%) |
| Number of Channels | 2 (simultaneous sampling) | 2 | 2 |
| SNR | 77 dB | 77 dB | 77 dB |
| SFDR | 90 dB | 90 dB | 90 dB |
| Output Interface | Serial LVDS (DDR, 1/2/4-bit modes) | Serial LVDS (DDR, 1/2/4-bit modes) | Serial LVDS (DDR, 1/2/4-bit modes) |
| Operating Temperature | -40C to +85C (I-grade) | 0C to +70C (C-grade) | -40C to +85C (I-grade) |
تفاوت‌های کلیدی
- Dual simultaneous-sampling channels at 40 Msps in a compact 52-pin QFN (7x8 mm) (در مقابلSingle-channel 16-bit ADCs in similar packages)
- DDR LVDS output with selectable 1-, 2-, or 4-bit-per-sample modes (در مقابلParallel CMOS-output 16-bit ADCs)
- Low power of approximately 80 mW total at full sample rate (در مقابلCompetitive 16-bit dual ADCs in similar packages)
یادداشت‌های طراحی
Layout must use a solid ground plane under the LTC2191IUKG with the exposed pad soldered to a low-inductance thermal/ground footprint. Place the 1.8 V analog decoupling (1 uF / 0.1 uF) within 5 mm of each VDD pin and surround each input pin pair with a ground guard ring. Differential input traces should be matched to within 0.5 mm to preserve the 77 dB SNR; any mismatch between AIN+ and AIN- paths converts directly to even-order distortion at the ADC output.
Common pitfalls include driving the analog inputs single-ended without biasing the common-mode voltage through VCM1/VCM2, which pushes the input outside the linear range and destroys SNR. The clock signal must be a clean differential sine or square from a low-jitter source (typical 250 fs RMS) as clock jitter directly limits SNR according to SNR = 6.02*N + 1.76 + 10*log10(FS/(2*pi*jitter)). Source-synchronous LVDS routing also requires matched lengths (within 50 ps) for setup/hold margin at the FPGA.
Enable the LTC2191IUKG's internal LVDS termination (per the 219210f datasheet) only when the FPGA receiver cannot supply 100 ohm termination near the input. For long board traces (>5 cm) leave termination off and place the 100 ohm differential termination at the receiver side. The serial-LVDS data rates in 2-bit and 4-bit modes exceed 1 Gbps, so controlled-impedance routing (100 ohm differential) and length-matched pairs are mandatory to avoid inter-symbol jitter.
اطلاعات انطباق
RoHS compliance and lead-free termination indicated by #PBF suffix. AEC-Q100 automotive qualification not stated in the provided data. REACH and conflict-minerals status taken from typical Linear Technology / Analog Devices declarations.
