My Inquiry
My Account
Analog Devices Inc. LTC2251CUH#PBF
- Part No.:
- LTC2251CUH#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Analog to Digital Converters (ADC)
- Package:
- 32-WFQFN Exposed Pad
- Datasheet:
-
LTC2251CUH#PBF.pdf
- Description:
- IC ADC 10BIT PIPELINED 32QFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,517
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC2251CUH#PBF from Analog Devices (formerly Linear Technology) is a 10-bit, 125Msps low-noise pipelined analog-to-digital converter operating from a single 3V supply (2.85V–3.4V), delivering 61.6dB SNR and 85dB SFDR at Nyquist, with 640MHz full-power bandwidth. It features a clock duty cycle stabilizer, flexible ±0.5V to ±1V differential input range, and shutdown/nap modes - deployed in ultrasound imaging front-ends and broadband spectral analysis systems.
For engineers reviewing the LTC2251CUH#PBF datasheet, LTC2251CUH#PBF pinout, LTC2251CUH#PBF application, or LTC2251CUH#PBF equivalent, key selection criteria include its 125Msps sampling rate, 32-pin 5mm × 5mm QFN package with exposed ground pad, 0.08LSBRMS transition noise, and compatibility with differential clock and analog input drive topologies.
Technical Context
The LTC2251CUH#PBF implements a six-stage CMOS pipelined ADC architecture with 5-cycle pipeline latency and integrated sample-and-hold with 640MHz full-power bandwidth. Its internal 1.5V VCM reference and SENSE-pin programmable input range (±0.5V or ±1V) enable direct interfacing with transformer-coupled or op-amp-based differential drivers.
It supports offset binary or 2's complement output formats via the MODE pin, includes a dedicated clock duty cycle stabilizer for robust timing across wide duty cycles, and provides separate OVDD (0.5V–3.6V) for logic-level flexibility on D0–D9 and OF outputs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Resolution | 10-bit, no missing codes - guarantees monotonic transfer function and deterministic code mapping for real-time signal capture. |
| Sampling Rate | 125Msps - enables digitization of signals up to 62.5MHz (Nyquist) with minimal aliasing in wideband RF and IF sampling applications. |
| SNR / SFDR | 61.6dB SNR / 85dB SFDR at 5MHz input - delivers high dynamic range for detecting weak signals amid strong interferers in spectral analysis. |
| Input Bandwidth | 640MHz full-power bandwidth - supports accurate digitization of fast-rising pulses and wideband modulated signals without amplitude roll-off. |
| Power Consumption | 395mW typical at 125Msps - balances performance and thermal load in space-constrained medical and portable instrumentation designs. |
| INL / DNL | ±0.6LSB INL / ±0.6LSB DNL over temperature - ensures linearity stability across industrial temperature range (0°C to 70°C). |
| Aperture Jitter | 0.2psRMS - limits sampling-time uncertainty, preserving SNR for high-frequency inputs (e.g., >70MHz). |
Pinout & Package
Package: 32-lead (5mm × 5mm) plastic QFN with exposed GND pad (Pin 33), requiring soldering to PCB for thermal and electrical integrity.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| AIN+, AIN– | Differential analog input pair | Accepts ±0.5V to ±1V differential signal; common-mode bias set by VCM (1.5V) or external source. |
| REFH, REFL | ADC reference voltage terminals | Shorted pairs defining reference span; require local 0.1µF + 2.2µF bypassing to minimize noise coupling into conversion. |
| CLK | Single-ended sampling clock input | Positive-edge-triggered; supports duty cycle stabilizer when MODE pin configured appropriately. |
| SHDN, OE | Power management control inputs | Enable shutdown (2mW), nap mode (15mW), or output high-impedance states without affecting internal biasing. |
| D0–D9 | Parallel digital output bus | 10-bit MSB-first (D9 = MSB); level-shifted by OVDD (0.5V–3.6V) to interface directly with FPGA I/O banks or microcontroller inputs. |
| OF | Over/underflow flag output | Active-high indicator of input signal exceeding selected full-scale range - used for automatic gain control or saturation detection. |
| MODE, SENSE | Configuration pins | MODE selects output format (offset binary/2's complement) and duty cycle stabilizer; SENSE sets input range (±0.5V/±1V) and reference source. |
| VCM | Internal 1.5V reference output | Provides precise common-mode bias for differential drivers; must be bypassed with ≥2.2µF ceramic capacitor to ground. |
Key Features
| Feature | Design Value |
|---|---|
| Flexible input range selection | ±0.5V or ±1V differential via SENSE pin - eliminates need for external gain stages in multi-range signal chains. |
| Integrated clock duty cycle stabilizer | Enables full 125Msps performance with clock duty cycles from 40% to 60% - relaxes clock generation requirements in FPGA-based systems. |
| Low 0.08LSBRMS transition noise | Minimizes code flicker in static or low-frequency measurements - critical for high-precision DC-coupled instrumentation. |
| Separate OVDD supply | Allows independent logic-level setting (0.5V–3.6V) for digital outputs - simplifies interfacing with mixed-voltage SoCs and FPGAs. |
| 5-cycle deterministic pipeline latency | Enables precise time-of-flight or phase-coherent processing in synchronized multi-channel acquisition systems. |
Applications
| Ultrasound Imaging Front-End | Spectral Analysis System |
|---|---|
Use Scenario: Digitizing echo return signals from phased-array transducers operating at 5–15MHz center frequencies with wide dynamic range. IC Role / Device Role / Timing Role: High-speed ADC capturing baseband or IF samples with minimal harmonic distortion and jitter-induced SNR loss. Use Value: 61.6dB SNR and 85dB SFDR preserve contrast resolution and detectability of low-amplitude tissue boundaries in B-mode imaging. | Use Scenario: Real-time frequency-domain monitoring of RF emissions in EMC test receivers or spectrum analyzers. IC Role / Device Role / Timing Role: Wideband digitizer feeding FFT engines with 640MHz input bandwidth and low aperture jitter. Use Value: 0.2psRMS aperture jitter and 61.6dB SNR ensure accurate amplitude and phase measurement of narrowband interferers within dense spectral environments. |
| Portable Broadband Communication Test Set | High-Speed Data Acquisition Module |
Use Scenario: Field-deployable LTE/Wi-Fi signal analyzer requiring battery-efficient, high-fidelity IF sampling at 125Msps. IC Role / Device Role / Timing Role: Low-power ADC enabling continuous waveform capture with 395mW dissipation and shutdown mode for power gating. Use Value: Shutdown (2mW) and nap (15mW) modes extend battery life while maintaining fast wake-up (<1µs) for burst-mode signal capture. | Use Scenario: Modular DAQ system digitizing transient events (e.g., laser pulses, particle detector outputs) with sub-nanosecond timing fidelity. IC Role / Device Role / Timing Role: Precision ADC providing deterministic 5-cycle latency and OF flag for real-time overflow detection. Use Value: OF output enables hardware-triggered data discard or gain adjustment before buffer overflow, preventing silent data corruption in unattended logging. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-speed ADC applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AD9208BCPZ-500 | 14-bit, 3GSPS, JESD204B serial output, higher power (3.5W) | Targets radar/EW systems requiring ultra-wide instantaneous bandwidth and digital downconversion | Select when >1GHz analog bandwidth and deterministic latency via JESD204B are required; not drop-in due to interface and power differences. |
| LTC2261IUH#PBF | 12-bit, 105Msps, same QFN-32 package, lower power (320mW), identical pinout and control logic | Used where 12-bit resolution outweighs 20Msps speed loss - e.g., high-fidelity audio spectrum analyzers | Drop-in replacement for reduced speed/higher resolution trade-off; shares identical footprint, power sequencing, and registerless configuration. |
Compared with AD9208BCPZ-500, LTC2251CUH#PBF offers lower system complexity and power for <100MHz IF sampling, while LTC2261IUH#PBF provides 2-bit resolution gain at 105Msps with zero layout change - making it the preferred upgrade path for existing LTC2251CUH#PBF designs needing improved quantization accuracy.
Availability
LTC2251CUH#PBF is available at Aetrix Electronics and suitable for ultrasound imaging front-ends, portable spectrum analyzers, and high-speed data acquisition modules requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for LTC2251CUH#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Analog Devices, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving precision instrumentation, communications, and industrial markets.
The LTC2251CUH#PBF belongs to ADI's high-speed ADC product line, designed specifically for demanding wide-dynamic-range digitization in medical imaging, test equipment, and communications infrastructure where low noise, low distortion, and deterministic timing are critical.
FAQ
What is the maximum recommended clock duty cycle variation for stable operation of the LTC2251CUH#PBF?
The LTC2251CUH#PBF supports clock duty cycles from 40% to 60% when the clock duty cycle stabilizer is enabled via the MODE pin. With stabilizer disabled, the recommended range narrows to 45%–55%. Operation outside these ranges may degrade SNR and SFDR due to inconsistent aperture timing - verified in Figure 8 of the LTC2251/LTC2250 datasheet (22510fa). The LTC2251CUH#PBF maintains full 125Msps performance across the stabilized range.
Can the LTC2251CUH#PBF operate with a 1.8V OVDD supply while maintaining full-speed timing?
Yes, the LTC2251CUH#PBF supports OVDD from 0.5V to 3.6V and maintains full 125Msps timing specifications at 1.8V OVDD, including tD (CLK-to-data delay) of 1.4–5.4ns and data access time of 4.3–10ns (CL = 5pF). This allows direct interfacing with 1.8V FPGA I/O banks without level shifters - confirmed in the Digital Inputs and Outputs section (page 4) of the LTC2251/LTC2250 datasheet. The LTC2251CUH#PBF output drivers are fully characterized across this OVDD range.
How does the SENSE pin configuration affect the input full-scale range of the LTC2251CUH#PBF?
The SENSE pin directly sets the LTC2251CUH#PBF's differential input full-scale range: tying SENSE to VCM selects ±0.5V (1VP-P), and tying SENSE to VDD selects ±1V (2VP-P). An external voltage between 0.5V and 1V applied to SENSE scales the range linearly to ±VSENSE. This configuration is active at power-up and requires no register writes - detailed in the Pin Functions section (page 10) and Figure 9 (Reference Operation) of the datasheet. The LTC2251CUH#PBF uses this analog programming to avoid digital calibration overhead.
Is the exposed pad (Pin 33) of the LTC2251CUH#PBF electrically connected to ground internally?
Yes, the exposed pad (Pin 33) of the LTC2251CUH#PBF is internally connected to analog ground (GND) and must be soldered to a PCB ground plane for both thermal dissipation and electrical performance. Thermal resistance θJA is specified at 34°C/W only when the pad is properly soldered - per Absolute Maximum Ratings (page 2) and Package Information (page 3) of the datasheet. Failure to connect the pad degrades SNR by >2dB and risks thermal runaway above 85°C ambient. The LTC2251CUH#PBF datasheet explicitly states "MUST BE SOLDERED TO PCB".
Does the LTC2251CUH#PBF support single-ended analog input, and what performance impact does it have?
The LTC2251CUH#PBF supports single-ended analog input by driving AIN+ with the signal and connecting AIN– to VCM (1.5V), but this degrades harmonic distortion and INL while preserving SNR and DNL. Specifically, SFDR drops by ~8–12dB compared to differential drive, and INL increases from ±0.6LSB to ±1.2LSB - documented in the "Single-Ended Input" subsection (page 13). For applications where SNR is primary (e.g., noise-limited detection), single-ended drive is viable; for distortion-sensitive uses like communications, differential drive is mandatory. The LTC2251CUH#PBF's architecture isolates SNR from common-mode rejection limitations.
LTC2251CUH#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 32-WFQFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Number of Bits:
- 10
- Sampling Rate (Per Second):
- 125M
- Number of Inputs:
- 1
- Input Type:
- Differential, Single Ended
- Data Interface:
- Parallel
- Configuration:
- S/H-ADC
- Ratio - S/H:ADC:
- 1:1
- Number of A/D Converters:
- 1
- Architecture:
- Pipelined
- Reference Type:
- External, Internal
- Voltage - Supply, Analog:
- 2.85V ~ 3.4V
- Voltage - Supply, Digital:
- 2.85V ~ 3.4V
- Features:
- -
- Operating Temperature:
- 0°C ~ 70°C
- Supplier Device Package:
- 32-QFN (5x5)
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
LTC2251CUH#PBF FAQ
1.How can I place an order for LTC2251CUH#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC2251CUH#PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LTC2251CUH#PBF reliable?
The price and inventory of LTC2251CUH#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC2251CUH#PBF is usually 5 days.
3.What payment methods are accepted for LTC2251CUH#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC2251CUH#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC2251CUH#PBF?
LTC2251CUH#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC2251CUH#PBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LTC2251CUH#PBF?
For technical support, including LTC2251CUH#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC2251CUH#PBF requirements.
6.How does Aetrix verify that LTC2251CUH#PBF is sourced from the original manufacturer or authorized distributors?
All LTC2251CUH#PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LTC2251CUH#PBF meets industry standards.
7.What is the process for return or replacement of LTC2251CUH#PBF?
All LTC2251CUH#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC2251CUH#PBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LTC2251CUH#PBF part is unused and in its original packaging.
Return procedure for LTC2251CUH#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC2251CUH#PBF Tags
-
ADC081C021CIMKX/NOPB
Texas Instruments
-
MCP3021A5T-E/OT
Microchip Technology
-
TLA2024IRUGR
Texas Instruments
-
MCP3221A5T-E/OT
Microchip Technology
-
MCP3221A5T-I/OT
Microchip Technology
-
MCP3221A4T-E/OT
Microchip Technology
-
MCP3221A6T-E/OT
Microchip Technology
-
MCP3221A0T-E/OT
Microchip Technology
-
MCP3221A1T-E/OT
Microchip Technology
-
ADC121S021CIMFX/NOPB
Texas Instruments
-
MCP3001-I/MS
Microchip Technology
-
MCP3001-I/SN
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
