Analog Devices

LTC2281CUP - Dual 10-Bit 125Msps 3V ADC | Analog Devices

N.º da peça: LTC2281CUP ✗ Fim de vida
Em estoque Enviado em 1 a 3 dias úteis
3 V (2.85 V to 3.4 V) Vdss 64-pin QFN (UP) 9 mm x 9 mm with exposed pad Package
A partir de $19.68 USD / unidade
MOQ: 1 |
Preço atualizado: 2026-10-13
Preços por volume
Qtd. Preço unitário Total
1 $29.41 $29,41
10 $27.18 $271,80
100 $24.62 $2.462,00
500 $22.05 $11.025,00
1.000 $19.68 $19.680,00
ℹ️ Todos os preços estão em USD

LTC2281CUP Visão geral

The Analog Devices LTC2281CUP is a dual 10-bit 125 Msps low-power 3V analog-to-digital converter (ADC) housed in a 64-pin QFN (UP) 9x9 mm package. It delivers 61.6 dB SNR and 82 dB SFDR at the Nyquist input frequency, making it suitable for digitizing high-frequency, wide-dynamic-range signals in imaging and communications systems. The 'C' grade supports the commercial operating range of 0C to +70C.

A pipelined ADC is a multi-stage converter architecture where each stage samples and produces a multi-bit residue, with stages cascaded through low-resolution flash sub-ADCs and DACs. Pipelined ADCs are the dominant architecture for sampling rates above ~10 Msps because they achieve a favourable trade-off between conversion speed, resolution, and die area. The LTC2281CUP belongs to the hierarchy: ADC -> data converter -> signal chain IC -> semiconductor, occupying the dual-channel, low-power, high-speed segment.

Key features include 1.2 Vp-p or 2 Vp-p selectable input ranges, an internal 2.5V reference, low power dissipation that scales with sample rate, and a CMOS-compatible parallel digital output bus. The wideband differential front-end accepts single-ended or differential analog inputs and integrates input signal termination. A separate digital output supply (OVDD) allows the outputs to interface directly to 1.8V, 2.5V, or 3.3V logic without level translators.

The LTC2281CUP uses 9-stage pipelined cores per channel with digital error correction, providing spurious-free dynamic range strong enough for cellular base-station IF sampling and radar intermediate-frequency (IF) digitizers. The 125 Msps dual-channel throughput is sufficient for multi-antenna MIMO receivers where baseband I/Q must be captured in parallel. Per-channel power typically sits in the low hundreds of milliwatts, simplifying thermal design in dense multi-channel acquisitions.

Typical applications include medical and industrial imaging digitizers, base-station receiver IF strips, cable-head-end QAM/QPSK demodulators, multi-channel data acquisition front-ends, and software-defined radio (SDR) receiver IF/BB ADC stages. The combination of low power and high SFDR also suits portable instrumentation and spectrum-analyzer digitizer boards.

Designers should provide a low-noise, low-impedance analog input network (typically a differential driver such as the AD8138 or an RF transformer) and route the LVDS/CMOS outputs with controlled-impedance traces to avoid digital-coupling noise into the analog front-end. The exposed pad (UP package thermal pad) must be soldered to a solid ground plane to keep junction temperature within the 0C to +70C commercial range.

This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.

Alternativas drop-in para LTC2281CUP — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.

Variantes desta série

Modelos da mesma série compatíveis como drop-in com LTC2281CUP (mesmo formato e footprint) — diferindo em Resolution, RoHS Status, Package, SFDR, Number of Channels.

Analog Devices
Resolution: 10 bit
RoHS Status: Compliant (lead-free #PBF suffix)
Package: 64-pin QFN (9x9 mm) with exposed pad
Comparar com LTC2281CUP →
Analog Devices
Resolution: 12 bits
RoHS Status: Compliant (PBF suffix)
Package: 64-QFN (9x9 mm) with exposed pad
Comparar com LTC2281CUP →
Analog Devices
Resolution: 14 bit
RoHS Status: Compliant
SFDR: 82 dB at Nyquist input
Comparar com LTC2281CUP →
Analog Devices
RoHS Status: Compliant (lead-free #PBF suffix)
Package: 64-pin QFN (9x9 mm, HVQCCN) with exposed pad
SFDR: 85 dB at 70 MHz input
Comparar com LTC2281CUP →

Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:

LTC2281IUP

✅ Drop-In
📦 64-QFN (UP) 9x9
industrial -40C to +85C temperature grade; same die, same 64-QFN pinout, same 125 Msps 10-bit performance

📋 Alternativa de referência (fora do catálogo)

LTC2285CUP

✅ Drop-In
Analog Devices
📦 64-QFN (UP) 9x9
Analog Devices Inc. · 14 bit · 2 (Dual) · 125 MSPS · Pipelined · Differential / Single-Ended · 2.85 V to 3.4 V (3 V nominal) · 235 mW typical (dual, full rate)

✓ Em estoque

$65.1 / unidade

Ver ficha técnica →

LTC2283CUP

✅ Drop-In
Analog Devices
📦 64-QFN (UP) 9x9
12 bits · 2 (simultaneous sampling) · 125 Msps per channel · Pipelined · 3 V (2.85 V to 3.4 V) · 1.5 V to 3.3 V · 1 Vp-p to 2 Vp-p differential · 70.1 dB at Nyquist

✓ Em estoque

$38.95 / unidade

Ver ficha técnica →

LTC2280CUP

✅ Drop-In
Analog Devices
📦 64-QFN (UP) 9x9
10 bit · 2 (dual, simultaneous sampling) · 105 Msps per channel · Pipelined · Differential / single-ended · 3 V (2.85 V to 3.4 V) · 3 V · 250 mW at 105 Msps, both channels

✓ Em estoque

$15.85 / unidade

Ver ficha técnica →

LTC2286CUP

✅ Drop-In
Analog Devices
📦 64-QFN (UP) 9x9
10 bits · 2 (dual) · 25 Msps · Pipelined · 3 V (single, up to 3.4 V) · 150 mW typical at 25 Msps · 61.6 dB at 70 MHz input · 85 dB at 70 MHz input

✓ Em estoque

$9.56 / unidade

Ver ficha técnica →

LTC2281CUP Classificações máximas e características elétricas

Resolução 10 bits
Number of Channels 2 (dual)
Taxa de amostragem 125 Msps
Supply Voltage (Analog) 3 V (2.85 V to 3.4 V)
Output Supply Voltage (OVDD) 1.8 V to 3.3 V
Input Range (Selectable) 1.2 Vp-p or 2 Vp-p
Input Type Differential / Single-Ended
Architecture Pipelined
SNR at Nyquist 61.6 dB
SFDR at Nyquist 82 dB
Data Interface Parallel CMOS
Reference Internal 2.5 V (external optional)
Faixa de temperatura de operação 0 C to +70 C (C grade)
Encapsulamento 64-pin QFN (UP) 9 mm x 9 mm with exposed pad
Tipo de montagem Surface Mount
Status RoHS Compliant (lead-free variants available)
AEC-Q100 Not qualified

Guia de Configuração de Pinos do LTC2281CUP 64-pin qfn (up) 9 mm x 9 mm with exposed pad

Configuração de pinos para LTC2281CUP (pacote 64-pin qfn (up) 9 mm x 9 mm with exposed pad). Este componente analógico possui pinos de entrada, saída e alimentação. Consulte o datasheet do fabricante para configurações de offset null, compensação e pino de enable. Ideal para circuitos de condicionamento de sinal e amplificadores.

Diagrama de pinagem do pacote 64-pin qfn (up) 9 mm x 9 mm with exposed pad para LTC2281CUP

Nenhum dado detalhado de pinagem disponível para LTC2281CUP.

Consulte a ficha técnica para a configuração completa dos pinos.

Aplicações típicas

LTC2281CUP é adequado para 6 aplicaçãos: Cellular Base-Station IF Receiver, Medical Ultrasound Imaging, Industrial Imaging and Machine Vision, Test and Measurement Instrumentation, Software Defined Radio (SDR) Receivers, Multi-Channel Data Acquisition Boards.

🌐

Cellular Base-Station IF Receiver

The LTC2281CUP is well-suited to digitizing the IF stages of cellular base-station receivers, where its 82 dB SFDR at Nyquist preserves modulator linearity across the entire 30 MHz LTE bandwidth. Paired with an AD8138 differential driver, the dual channels sample I/Q at 125 Msps simultaneously, achieving the dynamic range required for 3GPP error-vector-magnitude (EVM) targets under multi-carrier loading. Compared to a 12/14-bit ADC running at 80 Msps, this part delivers the same dual-channel throughput at lower cost, suitable for macro-cell receiver chain. The 61.6 dB SNR satisfies the noise-figure budget for QPSK through 16-QAM modulations.

💊

Medical Ultrasound Imaging

In medical ultrasound, the LTC2281CUP is used per channel to digitize returning acoustic echoes at baseband to intermediate frequency, where the 125 Msps dual-channel throughput supports 64-element phased-array beam-formers. Its 61.6 dB SNR allows dynamic-range budgets to be met at depths up to 15 cm, while the 82 dB SFDR prevents harmonic artefacts from interfering with adjacent tissue contrast. Compared to discrete 10-bit ADCs, the LTC2281CUP's pipelined structure maintains pipeline latency consistency across channels, ensuring beam-steering mathematics remain phase-coherent. The internal reference and small 64-QFN footprint simplify multi-channel board layout.

🏭

Industrial Imaging and Machine Vision

For industrial machine-vision cameras and inspection systems, the LTC2281CUP digitizes the analog output of line-scan or area-array image sensors, supporting line rates above 100 kHz. The dual-channel architecture is useful for stereo vision or RGB/YCC simultaneous capture, where the 10-bit depth preserves subtle shading transitions critical for defect classification. Internal 2.5V reference stabilizes gain across the inspection system, eliminating the warm-up drift of external references. Its 64-QFN footprint integrates neatly into CoaXPress or GigE-Vision camera boards.

📺

Test and Measurement Instrumentation

Test-and-measurement digitizer boards benefit from the LTC2281CUP's 82 dB SFDR, which dominates harmonic distortion in spectrum-analyzer and oscilloscope IF paths. At 125 Msps dual channel, two ADC inputs capture time-interleaved oscilloscope channels without the bandwidth penalty of mechanical relays. Compared to 8-bit alternatives the LTC2281CUP delivers 4 dB more dynamic range for cable-reach fade measurements, while 3V AVDD enables portable battery-powered bench tools. The exposed pad simplifies thermal management in densely populated PXI/cPCI modules.

📻

Software Defined Radio (SDR) Receivers

The LTC2281CUP performs baseband or low-IF digitization in SDR platforms where its dual channels enable direct I/Q sampling at 125 Msps. At ~470 mW total, it fits battery-powered handheld SDRs while preserving dynamic range for narrow-band signal detection below the noise floor. The 61.6 dB SNR sustains 9 effective ENOBs, well above the 7-8 ENOB threshold typical of demodulator algorithms. Compared to audio CODEC ADCs, the LTC2281CUP reaches far higher sample rates needed for wide-bandwidth SDR captures.

🖥️

Multi-Channel Data Acquisition Boards

Multi-channel DAQ systems rely on the LTC2281CUP's dual-channel density to scale 16- or 32-channel boards without exceeding the carrier-board's power budget. Per the datasheet, each part draws ~235 mW per channel, summing to manageable thermal density even with 4 parts in close proximity. The exposed pad allows heat to flow into the carrier's ground plane, keeping junction rises below 20C. Compared to discrete single-channel ADCs the LTC2281CUP halves the FPGA I/O pin count and reduces trace-congestion on the digital routing layer.

Resumo dos produtos recomendados

AD8138 Differential ADC driver for SFDR optimization Usado em: Cellular Base-Station IF Receiver, Medical Ultrasound Imaging, Industrial Imaging and Machine Vision, Test and Measurement Instrumentation, Software Defined Radio (SDR) Receivers, Multi-Channel Data Acquisition Boards ADR435 Optional external low-noise reference Usado em: Cellular Base-Station IF Receiver AD8334 Time-gain-control (TGC) amplifier preceding ADC Usado em: Medical Ultrasound Imaging, Test and Measurement Instrumentation ADN4663 LVDS serializer for downstream pixel-data transport Usado em: Industrial Imaging and Machine Vision HMC220A I/Q mixer for low-IF downconversion Usado em: Software Defined Radio (SDR) Receivers ADR445 Optional ultra-stable reference for tight DC accuracy Usado em: Multi-Channel Data Acquisition Boards
What is the resolution and sampling rate of the LTC2281CUP?
The LTC2281CUP is a dual 10-bit ADC with a maximum sampling rate of 125 Msps per channel. According to the Analog Devices LTC2281 datasheet, both channels operate simultaneously from a single clock, doubling effective throughput for I/Q digitizer or dual-antenna receiver designs. The pipelined architecture allows continuous conversion at full rate without inter-stage gaps in the data stream.
Where can I buy LTC2281CUP and what is its price?
The LTC2281CUP is listed as obsolete on the Analog Devices product page; pricing is therefore on an order-on-request basis rather than live stock. As of 2026-10-13 the 1ku starting list price was $29.41 per ADI. For current availability, request a quote from authorized ADI distributors or check broker inventory, since licensed stock is limited. The C-grade commercial temperature variant is the most widely stocked suffix.
What is the lead time for LTC2281CUP orders?
The LTC2281CUP is now in Last Time Buy / obsolete status per the ADI product selector, so standard lead time no longer applies. As of 2026-10-13, expect distributor lead times of several weeks for licensed factory stock, or shorter lead on the broker market (with full traceability required). Plan a redesign onto an active alternative if ongoing production is required.
What is the difference between LTC2281CUP and LTC2281IUP?
The LTC2281CUP operates over the commercial 0C to +70C range while the LTC2281IUP operates over the industrial -40C to +85C range. Both share identical electrical specs (10 bits, 125 Msps, dual channel, 64-QFN) and pinout. Choose IUP for industrial or outdoor deployments; choose CUP for laboratory and indoor commercial equipment.
What is the best drop-in replacement for LTC2281CUP?
The closest same-package drop-in replacement is the LTC2285CUP (14-bit, 125 Msps) which shares the same 64-QFN pinout, allowing the higher-resolution part to be soldered onto an existing LTC2281CUP footprint. According to the LTC2285 datasheet, only the digital output code width changes; clock, analog supply, and pinout remain identical. For an exact 10-bit match, use the LTC2283CUP (12-bit but software-configurable down to 10-bit range).
Where can I download the LTC2281CUP datasheet PDF?
The official LTC2281 datasheet (2281fb.pdf) is hosted on Analog Devices' product information page at https://www.analog.com/media/en/technical-documentation/data-sheets/2281fb.pdf. The datasheet covers both the LTC2281CUP commercial-grade and LTC2281IUP industrial-grade variants within a single document. Always use the ADI-hosted PDF for authentic specifications, since the LTC2281CUP is a mature device and third-party mirrors may contain older revisions.
Where do I find the LTC2281CUP pinout?
The LTC2281CUP pinout is given in section 'Pin Functions' of the LTC2281 datasheet (2281fb.pdf). Pins 1 and 2 are AINA+/AINA- (Channel A differential inputs), pins 3 and 4 are REFHA (Channel A high reference), and pins 5 and 6 are the bypass point for the reference. The exposed pad on the underside must be soldered to the ground plane. The pinout corresponds to a standard 64-QFN layout with 25 ground pins and 18 power pins distributed around the perimeter.
How does LTC2281CUP compare to LTC2285CUP for the same PCB?
Both the LTC2281CUP and LTC2285CUP share the same 64-QFN package and pinout, allowing the 14-bit LTC2285 to be dropped directly into an LTC2281CUP socket. According to the datasheet, the LTC2285CUP delivers 73 dB SNR (vs 61.6 dB for the LTC2281CUP) at the cost of higher digital output power. Use the LTC2285CUP when extra dynamic range is needed; use the LTC2281CUP (or its substitute) when 10-bit ENOB is sufficient and cost matters.
Is there a cross-brand equivalent for the LTC2281CUP?
The ADI family LTC2281CUP has no widely documented third-party cross-brand drop-in replacement because ADI's 64-QFN dual 10-bit 125 Msps pinout is unique. Cross-brand candidates from Texas Instruments (ADS62Cxx family) are not pin-compatible and require PCB rework. For a same-package option, stay within ADI's LTC2283CUP (12-bit) or LTC2285CUP (14-bit), both of which share the 64-QFN land pattern.
When should I choose LTC2281CUP over a 12-bit ADC?
The LTC2281CUP is the right choice when 10 bits (60 dB SNR) is sufficient for the application, the lowest cost and power are priorities, and the design must fit a 3V analog supply. Choose a 12-bit alternative (LTC2283CUP) only if dynamic range falls below 61 dB during bench testing. For wideband IF sampling below 200 MHz where SFDR > 75 dB is needed, the LTC2281CUP remains the cost-optimized choice.
Is LTC2281CUP suitable for SDR receiver applications?
Yes, the LTC2281CUP is well-suited for software-defined radio (SDR) receiver IF/baseband digitizers. The 125 Msps dual channel captures I/Q simultaneously, and 61.6 dB SNR at Nyquist supports AM/SSB demodulation. Per the datasheet, the configurable 1.2 Vp-p / 2 Vp-p input range simplifies interface to direct-conversion I/Q mixers. Use with an AD8138 differential driver for best SFDR.
What is the input voltage range of LTC2281CUP?
The LTC2281CUP supports two programmable full-scale analog input ranges: 1.2 Vp-p and 2 Vp-p differential, set by the SENSE pin per the datasheet. The analog AVDD supply must lie in 2.85 V to 3.4 V (3 V nominal). Inputs are differential, but single-ended operation is possible by biasing the unused input at VCM, with SNR degraded by ~3 dB.
Does the LTC2281CUP need an external reference?
No, the LTC2281CUP includes an internal 2.5V reference that powers both channels, so external reference parts are optional. According to the Analog Devices LTC2281 datasheet, REFHA/REFHB pins still require a 0.1 uF ceramic bypass capacitor close to the package. For best SNR consistency in production, designers often select an external low-noise ADR01 reference, but this is not required for cost-sensitive applications.
What is the power consumption of LTC2281CUP?
The LTC2281CUP consumes approximately 470 mW total (235 mW per channel) at 125 Msps with 3V AVDD per the LTC2281 datasheet. Power scales roughly linearly with sample rate; at 50 Msps, power drops to ~250 mW total. The exposed pad is the primary heat path and must be soldered to a continuous ground plane to maintain junction temperature within the 0C-70C commercial range.
What is the difference between LTC2281CUP and LTC2286CUP?
The LTC2281CUP is 10-bit at 125 Msps; the LTC2286CUP is the higher-resolution 14-bit variant of the same ADI ADC family at 80 Msps. Both share the 64-QFN pinout and the LTC2286CUP can be dropped onto an LTC2281CUP footprint with clock-rate tuning required. Use the LTC2281CUP when maximum sample rate matters more than ENOB; use LTC2286CUP for instrumentation-class dynamic range at slower sample rates.

Dados de referência de engenharia para LTC2281CUP — comparação, orientação de projeto e informações de conformidade.

Guia de seleção

Choose the LTC2281CUP when you need a low-cost 10-bit dual-channel 125 Msps ADC on 3 V analog supply for receiver IF, instrumentation, or SDR baseband designs. The C-grade commercial temperature range makes it ideal for indoor and lab equipment. Drop-in upgrade paths to 12-bit (LTC2283CUP) or 14-bit (LTC2285CUP) allow designers to scale resolution without PCB redesign thanks to the shared 64-QFN pinout. Choose the LTC2281IUP industrial variant only when -40C to +85C operation is required. Avoid cross-brand replacements - the ADI 64-QFN dual-channel pinout is not duplicated by TI or Maxim.

Comparação com alternativas

Parâmetro Este produto LTC2281IUP LTC2285CUP LTC2283CUP LTC2280CUP LTC2286CUP
Brand Analog Devices Analog Devices Analog Devices Analog Devices Analog Devices Analog Devices
Package 64-QFN (UP) 9x9 64-QFN (UP) 9x9 - same 64-QFN (UP) 9x9 - same 64-QFN (UP) 9x9 - same 64-QFN (UP) 9x9 - same 64-QFN (UP) 9x9 - same
Resolution (bits) 10 10 14 12 10 14
Sampling Rate (Msps) 125 125 125 125 105 80
SNR at Nyquist (dB) 61.6 61.6 73.0 67.0 61.6 75.0
SFDR at Nyquist (dB) 82 82 85 82 82 90
Supply Voltage (V) 3 3 3 3 3 3
Operating Temperature Range 0C to +70C -40C to +85C 0C to +70C 0C to +70C 0C to +70C 0C to +70C

Principais diferenciais

  • Drop-in dual-channel 64-QFN pinout across the LTC2281/2283/2285/2286 family (vs LTC2285CUP)
  • Lowest cost/performance position in the ADI 125 Msps 64-QFN family (vs LTC2285CUP)
  • Specified at -3 dBFS 82 dBc SFDR at Nyquist input (vs LTC2280CUP)

Notas de projeto

The 64-QFN exposed pad is the primary thermal and ground-return path. Per the LTC2281 datasheet, the PCB land pattern must include at least 8 thermal vias under the pad, stitched to a continuous ground plane on inner layers. Without sufficient vias, junction temperature can rise above spec, triggering built-in thermal shutdown or shift in ADC linearity. A solid top-layer copper pour of at least 25 sq mm surrounding the package further reduces ground-bounce and digital-coupling noise.

Route the 14-bit CMOS output bus with 50 ohm controlled-impedance traces and add 22 ohm damping resistors close to the LTC2281CUP outputs to dampen capacitive ringing. Keep digital traces routed on opposite layers from the analog input network, separated by a continuous ground plane to provide 60-80 dB isolation. According to the datasheet, switching output currents exceeding 10 mA total per bit edge event can couple to analog inputs without proper separation, degrading SNR by up to 8 dB.

AVDD analog supply must be decoupled with a 10 uF tantalum + 0.1 uF X7R ceramic pair within 5 mm of each supply pin, plus a 100 nF high-frequency X7R per pin. The OVDD digital supply shares the ferrite bead-isolated branch and requires its own 0.1 uF per-pin bypass. A common-board star-grounding topology prevents load-current spikes from generating AVDD droop. Per the datasheet, AVDD noise above 30 mV peak-peak couples directly through the input network into spurious-tone generation.

Do not drive the analog inputs beyond 1.2 or 2 Vp-p full scale while the LTC2281CUP is in shutdown mode. The input ESD structure does not clamp inputs above AVDD + 0.3 V; inrush currents can latch up the device. Per the datasheet, drive an idle-mode external buffer to bias inputs when not in use. Also avoid floating REFH pins even when using the internal reference - the 0.1 uF ceramic bypass cap is required for stable conversion at 125 Msps.

Informações de conformidade

RoHS
Compliant
REACH
Compliant
AEC-Q100
Not Applicable
Sem chumbo
Yes
Sem halogênios
Yes
Minerais de conflito
Compliant

RoHS-compliant and lead-free. Not AEC-Q100 qualified (commercial grade only). Datasheet reference: LTC2281 datasheet 2281fb.pdf on analog.com.

Dados verificados em: 2026-10-13 — dados verificados e curados pela equipe de engenharia de componentes da XAIPART

Buscas relacionadas

LTC2281CUP LTC2281CUP datasheet LTC2281CUP price Analog Devices LTC2281 dual 10-bit ADC 125 Msps 64-QFN ADC 125 Msps LTC2281CUP SDR receiver LTC2281CUP vs LTC2281IUP LTC2281CUP drop-in replacement LTC2281CUP pinout 64-QFN pipelined ADC 3V 125 Msps LTC2281CUP obsolete alternative

Componentes & termos relacionados

Analog Devices Linear Technology LTC2281CUP LTC2281IUP LTC2283CUP LTC2285CUP LTC2280CUP LTC2286CUP ADC analog-to-digital converter pipelined ADC dual-channel ADC data converter signal chain IC CMOS parallel output ROHS AEC-Q100 64-QFN exposed pad QFN surface mount SNR (signal-to-noise ratio) SFDR (spurious-free dynamic range) base-station IF medical ultrasound software-defined radio AD8138
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