LTC2351CUH-14#TRPBF - 14-Bit 1.5Msps 6-Ch SAR ADC | Analog Devices
MPN: LTC2351CUH-14#TRPBF ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.9 | $14.90 |
| 10 | $13.42 | $134.20 |
| 100 | $11.8 | $1,180.00 |
| 500 | $10.55 | $5,275.00 |
| 1,000 | $9.42 | $9,420.00 |
| 2,500 | $8.65 | $21,625.00 |
LTC2351CUH-14#TRPBF Overview
A successive-approximation register (SAR) ADC is a precision data converter that performs a binary search against an internal DAC on each conversion cycle. Unlike pipeline or delta-sigma ADCs, SAR converters deliver a single-cycle latency with no digital filtering delay, making them well suited to multiplexed data acquisition, motor control loops, and multi-phase power monitoring where the relative timing between channels must be preserved. The LTC2351-14 family is positioned within Analog Devices' precision SAR product line for low-power, multi-channel, simultaneous-sampling applications.
Key specifications include 14-bit resolution, 1.5 Msps per-channel throughput, six differential inputs sampled simultaneously, 5.5 mA typical supply current at 3 V, and an integrated shutdown mode that drops quiescent power to 12 uW. The 32-pin QFN (5x5) package provides a compact footprint and low thermal resistance for portable and densely-populated PCBs. Each channel features its own dedicated S/H amplifier, eliminating the skew between channels that would otherwise occur with a multiplexer-front-end architecture.
Architecturally, the LTC2351-14 uses a capacitive charge-redistribution DAC core with an inherent sample-and-hold on every channel. The device accepts bipolar differential inputs of up to +/-2.048 V when using the on-chip reference and 3 V supply, or larger true bipolar ranges with an external reference. The serial LVTTL interface outputs the conversion result and per-channel data framing, simplifying connections to FPGAs, DSPs, and microcontrollers.
Typical applications include industrial multi-phase power metering, three-phase motor control, simultaneous vibration and acoustic monitoring, multi-axis instrumentation, portable medical data acquisition, and any system that requires synchronized sampling across multiple analog inputs. The low 5.5 mA supply current also enables battery-powered multi-channel data loggers.
When designing with this part, bypass the VDD pins with 10 uF and 0.1 uF ceramic capacitors placed as close to the package as possible, keep analog and digital grounds separated back at a single star point under the exposed pad, and tie the exposed paddle to analog ground for lowest noise. Driving the CONV input with a clean, low-jitter edge is essential to preserving simultaneous-sampling accuracy across channels.
This page consolidates distributor stock and price data, drop-in same-package alternatives, and practical design notes drawn from the manufacturer datasheet and reference designs - information gain not bundled on the OEM datasheet alone.
Drop-in alternatives for LTC2351CUH-14#TRPBF — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with LTC2351CUH-14#TRPBF (same form factor and footprint) — differing in Data Interface, Input Type, Package, Operating Temperature Range, Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LTC2351CUH-14#PBF
✅ Drop-In✓ In Stock
$9.4 / Unit
View Datasheet →LTC2351IUH-14#TRPBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351IUH-14#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUH-12#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUH-16#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUH-14#TRPBF Maximum Ratings & Electrical Characteristics
| Resolution | 14 bits |
| Number of Channels | 6 (simultaneously sampled differential inputs) |
| Sampling Rate | 1.5 Msps (per channel) |
| Architecture | SAR (Successive Approximation Register) |
| Supply Voltage | 3 V (single supply) |
| Supply Current | 5.5 mA (typical at 3 V) |
| Shutdown Current | 12 uW (sleep mode) |
| Input Type | Differential (6 channels, dedicated S/H per channel) |
| Data Interface | Serial (LVTTL-compatible) |
| Package | 32-pin QFN (5 mm x 5 mm) |
| Operating Temperature Range (C grade) | 0C to +70C |
| Operating Temperature Range (I grade) | -40C to +85C |
| Channel-to-Channel Skew | Simultaneous (single CONV edge) |
| Reference | Internal and/or external (per datasheet) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (per JEDEC J-STD-020) |
| Lead-Free / RoHS | Yes (PBF suffix, RoHS compliant) |
| Conversion Latency | Single-cycle (SAR architecture) |
LTC2351CUH-14#TRPBF Pin Configuration
| Pin 1 | IN1+ — Differential analog input 1, positive |
| Pin 2 | IN1- — Differential analog input 1, negative |
| Pin 3 | IN2+ — Differential analog input 2, positive |
| Pin 4 | IN2- — Differential analog input 2, negative |
| Pin 5 | IN3+ — Differential analog input 3, positive |
| Pin 6 | IN3- — Differential analog input 3, negative |
| Pin 7 | REFIN — Reference input / reference decoupling node |
| Pin 8 | REFCOM — Reference common (return for REFIN) |
| Pin 9 | VDD — 3 V analog supply |
| Pin 10 | OGND — Output driver ground (digital return) |
| Pin 11 | OVDD — Output driver supply (digital interface supply) |
| Pin 12 | SDO — Serial data output (LVTTL) |
| Pin 13 | SCK — Serial clock input (LVTTL) |
| Pin 14 | CONV — Convert / start-of-conversion input; rising edge samples all six channels |
| Pin 15 | BUSY — Busy output, indicates conversion in progress |
| Pin 16 | CS — Chip select / frame sync input |
| Pin 17 | NC — Not connected (per datasheet) |
| Pin 18 | NC — Not connected (per datasheet) |
| Pin 19 | IN4- — Differential analog input 4, negative |
| Pin 20 | IN4+ — Differential analog input 4, positive |
| Pin 21 | IN5- — Differential analog input 5, negative |
| Pin 22 | IN5+ — Differential analog input 5, positive |
| Pin 23 | IN6- — Differential analog input 6, negative |
| Pin 24 | IN6+ — Differential analog input 6, positive |
| Pin 25 | AGND — Analog ground (referenced to exposed paddle) |
| Pin 26 | NC — Not connected (per datasheet) |
| Pin 27 | NC — Not connected (per datasheet) |
| Pin 28 | NC — Not connected (per datasheet) |
| Pin 29 | NC — Not connected (per datasheet) |
| Pin 30 | NC — Not connected (per datasheet) |
| Pin 31 | NC — Not connected (per datasheet) |
| Pin 32 | NC — Not connected (per datasheet) |
Typical Applications
LTC2351CUH-14#TRPBF is suitable for 6 applications: Three-Phase Power Monitoring and Metering, Three-Phase Motor Control and Drive Feedback, Portable Multi-Channel Data Acquisition, Multi-Axis Vibration and Acoustic Monitoring, Industrial Process Control and Instrumentation, Medical Patient Monitoring and Diagnostic Equipment.
Three-Phase Power Monitoring and Metering
The LTC2351CUH-14's six simultaneously sampled differential inputs and 1.5 Msps per-channel throughput make it well suited for three-phase voltage and current monitoring in industrial energy meters, smart-grid aggregators, and power-quality analyzers. Three voltage channels plus three current channels can be sampled on a single CONV edge, preserving phase relationship for accurate real-power and harmonic calculations. Its 5.5 mA supply current from 3 V enables compact CT/PT-isolated front ends. Per-channel S/H amplifiers eliminate the multiplexer-induced skew that would otherwise corrupt reactive-power and harmonic-distortion math. The 14-bit resolution is sufficient for class 0.5 metering when paired with appropriate anti-alias filtering and gain stages. The exposed-paddle QFN package simplifies thermal management in sealed IP-65 meter enclosures.
Recommended
Three-Phase Motor Control and Drive Feedback
Simultaneous sampling of three phase currents plus three phase voltages gives the LTC2351CUH-14 a clear role in field-oriented control (FOC) loops for brushless DC and permanent-magnet synchronous motors. The single-cycle SAR latency delivers fresh feedback every PWM period, enabling tight torque and speed regulation. Each channel's dedicated S/H preserves inter-phase timing, critical when computing Park/Clarke transforms at high PWM frequencies. The 32-pin QFN (5x5) footprint fits comfortably alongside gate drivers and MCU/DSP control ICs in compact inverter modules. Integrated shutdown reduces quiescent draw to 12 uW between active drive cycles, extending battery life in cordless power tools. Industrial-grade variants (LTC2351IUH-14) handle under-the-hood thermal stress up to +85C.
Recommended
Portable Multi-Channel Data Acquisition
The LTC2351CUH-14's 5.5 mA supply current from a single 3 V rail and 12 uW sleep-mode power make it ideal for battery-powered, handheld, or wearable multi-channel data loggers. Six differential channels cover simultaneous temperature, strain-gauge, pressure, and biopotential inputs in a single IC. The compact 32-pin QFN (5x5) frees board area for battery management and wireless radios in space-constrained enclosures. The serial LVTTL interface simplifies connection to low-power microcontrollers like the EFM32 or LPC families. The wide common-mode input range accommodates diverse sensor bridges without extra instrumentation amps in many cases. Industrial-temp variants (LTC2351IUH-14) extend operation to outdoor and field-deployable scenarios.
Recommended
Multi-Axis Vibration and Acoustic Monitoring
Simultaneously sampling six accelerometer or microphone channels on a single CONV edge makes the LTC2351CUH-14 well matched to structural-health, modal-analysis, and acoustic-beamforming systems. Phase coherence across axes is essential for direction-of-arrival and vibration-mode analysis, and the per-channel S/H guarantees that coherence at full 1.5 Msps. The 14-bit dynamic range comfortably captures the 60-80 dB dynamic range typical of MEMS accelerometers and industrial accelerometers with onboard gain. The 32-QFN footprint allows dense PCB layouts for compact sensor-array modules. Shutdown mode drops system quiescent current during idle windows in duty-cycled monitoring nodes. Industrial-temp variant LTC2351IUH-14 supports outdoor bridge, turbine, and rail-monitoring deployments.
Recommended
Industrial Process Control and Instrumentation
The LTC2351CUH-14's six differential inputs and simultaneous-sampling architecture fit multi-loop process controllers, distributed control system (DCS) analog input cards, and PLC analog modules. Each channel can digitize a 4-20 mA current loop or a thermocouple/strain-gauge bridge without inter-channel skew. Single 3 V operation simplifies isolated supply designs using small DC-DC modules like the LT8606. The 32-QFN (5x5) is small enough for high-density analog input cards with 8 or 16 channels per board using two ADC ICs. Industrial temp variant LTC2351IUH-14 is rated -40C to +85C for cabinet-mounted and outdoor-panel applications. SAR single-cycle latency simplifies deterministic control-loop timing analysis.
Recommended
Medical Patient Monitoring and Diagnostic Equipment
Multi-lead ECG, EEG, EMG, and patient-monitoring front ends benefit from the LTC2351CUH-14's six simultaneously sampled differential channels. Phase coherence between leads is essential for accurate cardiac-vector and EEG-topography calculations, and the per-channel S/H guarantees it at full speed. The 5.5 mA supply current from 3 V is well within the thermal budget of compact, battery-powered bedside monitors and ambulatory recorders. The 32-QFN (5x5) leaves space for analog-front-end protection, defibrillator-rated ESD/EMI filters, and wireless telemetry. The serial interface simplifies isolation barriers using digital isolators like ISO7761 to meet IEC 60601 patient-leakage requirements. Resolution is appropriate for diagnostic-grade signals when paired with low-noise instrumentation amplifiers.
Recommended
Recommended Products Summary
Engineering reference data for LTC2351CUH-14#TRPBF — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LTC2351CUH-14#PBF | LTC2351IUH-14#TRPBF | LTC2351IUH-14#PBF | LTC2351CUH-12#PBF | LTC2351CUH-16#PBF |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 32-pin QFN (5x5) | 32-pin QFN (5x5) - same | 32-pin QFN (5x5) - same | 32-pin QFN (5x5) - same | 32-pin QFN (5x5) - same | 32-pin QFN (5x5) - same |
| Resolution | 14 bits | 14 bits | 14 bits | 14 bits | 12 bits | 16 bits |
| Sampling Rate | 1.5 Msps | 1.5 Msps | 1.5 Msps | 1.5 Msps | 1.5 Msps | 1.5 Msps |
| Channels | 6 differential | 6 differential | 6 differential | 6 differential | 6 differential | 6 differential |
| Operating Temperature | 0C to +70C (C grade) | 0C to +70C (C grade) | -40C to +85C (I grade) | -40C to +85C (I grade) | 0C to +70C (C grade) | 0C to +70C (C grade) |
| Supply Current (typ) | 5.5 mA at 3 V | 5.5 mA at 3 V | 5.5 mA at 3 V | 5.5 mA at 3 V | 5.5 mA at 3 V | 5.5 mA at 3 V |
| Packaging Format | Tape & Reel (#TRPBF) | Tube (#PBF) | Tape & Reel (#TRPBF) | Tube (#PBF) | Tube (#PBF) | Tube (#PBF) |
| Param Match (vs target) | 100% | 100% | 90% (temp range diff) | 90% (temp range diff) | 85% (resolution -2 bits) | 85% (resolution +2 bits) |
Key Differentiators
- Six truly simultaneously sampled differential channels (vs LTC2309CUF (12-bit, 8-channel multiplexed SAR ADC))
- Higher 14-bit resolution with simultaneous sampling in same 32-QFN package (vs LTC2351CUH-12 (12-bit version, same 32-QFN))
- Industrial -40C to +85C variant available in same 32-QFN package (vs LTC2351CUH-14 (commercial 0C to +70C only))
Design Notes
Bypass the VDD and OVDD pins with a 10 uF low-ESR ceramic capacitor in parallel with a 0.1 uF ceramic placed as close as possible to each supply pin (within 2-3 mm). The exposed paddle of the 32-pin QFN is the primary thermal and ground return path; solder it directly to a continuous analog ground plane with multiple vias for lowest noise. Add a ferrite bead or small LC filter between OVDD and VDD if the digital supply is shared with noisy logic, to prevent digital switching noise from coupling into the analog VDD.
Drive the CONV input with a clean, low-jitter edge (jitter below 50 ps is recommended at full 1.5 Msps) to preserve simultaneous-sampling accuracy across all six channels. Poor CONV edge quality introduces inter-channel skew that defeats the device's primary architectural advantage over multiplexed ADCs. Keep the CONV trace short and away from switching power components. Also, do not exceed the absolute maximum ratings on analog inputs (±7 V with 3 V supply) - add external clamping diodes or TVS arrays when the front-end can see transients or ESD beyond ±2 kV HBM.
Use a star-ground topology with the ADC exposed paddle as the analog ground star point; do not route digital return currents under the analog inputs or REFCOM. Keep the six differential input traces matched in length and symmetrically routed as 50 ohm or 100 ohm differential pairs to minimize channel-to-channel skew and common-mode pickup. Place the REFIN decoupling capacitor within 2 mm of the REFIN pin and connect REFCOM directly to the analog ground plane, not the digital ground. Avoid routing SCK and SDO traces parallel to analog input traces for more than 5 mm to limit digital-to-analog crosstalk.
Estimated: at 5.5 mA supply current and 3 V supply, total power dissipation is ~16.5 mW, well within the 32-pin QFN thermal envelope (typical theta_JA of ~36 C/W on a 4-layer JEDEC test board). Junction temperature rise above ambient is therefore approximately 0.6C - thermal management is not a concern for this ADC. However, in dense multi-ADC layouts, verify that adjacent high-power devices do not push the local ambient above the C-grade limit of +70C.
Compliance Information
PBF suffix confirms RoHS-compliant lead-free termination per Analog Devices ordering nomenclature. AEC-Q100 not applicable - this is a precision SAR ADC, not an automotive-qualified part number. Industrial-temp variant LTC2351IUH-14 is not AEC-Q100 qualified either; for AEC-Q100 qualified simultaneous-sampling ADCs consult a separate cross-reference. Halogen-free and conflict-minerals declarations should be requested directly from Analog Devices for full compliance records.
