LTC2351CUH-14 - 14-Bit 1.5Msps 6-Ch Simultaneous-Sampling ADC | ADI
MPN: LTC2351CUH-14 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $17.2 | $172.00 |
| 100 | $15.5 | $1,550.00 |
| 500 | $13.8 | $6,900.00 |
| 1,000 | $12.4 | $12,400.00 |
LTC2351CUH-14 Overview
An ADC (Analog-to-Digital Converter) is a mixed-signal integrated circuit that converts continuous analog voltages into discrete digital codes for processing by microcontrollers, DSPs, or FPGAs. Multi-channel simultaneous-sampling ADCs such as the LTC2351CUH-14 are a specialized subclass of successive-approximation-register (SAR) ADCs designed for applications where the relative phase between channels must be preserved — for example, three-phase power monitoring, multi-axis vibration analysis, and phased-array beamforming. The LTC2351CUH-14 belongs to the power management and signal-chain IC hierarchy: ADC -> data converter -> mixed-signal IC -> semiconductor.
Key features of the LTC2351CUH-14 include six differential input channels sampled simultaneously at up to 1.5Msps per channel, a single 3V analog supply operation, 12uW sleep-mode power, and an integrated track-and-hold per channel. The device accepts differential inputs well suited to bridge sensors, current shunts, and direct connection to operational amplifiers. Its 32-lead 5x5mm QFN package provides a compact footprint suitable for portable instrumentation and high-density PCB layouts.
The LTC2351CUH-14 is built on a low-power CMOS SAR architecture with internal reference and six dedicated sample-and-hold amplifiers that capture all channel voltages on the same clock edge, eliminating inter-channel skew. A standard SPI/serial interface streams conversion results to the host controller, and a dedicated CONVST pin initiates conversion across all six channels synchronously.
Typical applications include three-phase power-quality monitoring, multi-axis industrial vibration analysis, portable medical instrumentation, simultaneous multi-sensor data acquisition, phased-array ultrasound receivers, and multi-channel sonar / radar front-ends. The wide dynamic range and low power make the part suitable for both battery-powered and line-powered instruments.
When designing with the LTC2351CUH-14, ensure the analog input common-mode voltage lies within the input range of the SAR core, and add anti-alias filtering on each differential pair. Decouple the 3V analog supply with a 10uF ceramic + 0.1uF X7R combination placed within 5mm of the supply pin to minimize ADC reference noise and improve spurious performance.
This page synthesizes verified distributor pricing, drop-in alternative MPNs, and practical design notes drawn from the manufacturer datasheet and reference designs - content not consolidated on distributor product pages.
Drop-in alternatives for LTC2351CUH-14 — 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 (same form factor and footprint) — differing in Data Interface, Package, Architecture, Input Type, Resolution.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LTC2351IUH-14#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUH-14#TRPBF
✅ Drop-In✓ In Stock
$8.65 / Unit
View Datasheet →LTC2351IUH-14#TRPBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUK-14#PBF
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
LTC2351CUH-14 Maximum Ratings & Electrical Characteristics
| Resolution | 14 bit |
| Number of Channels | 6 (simultaneously sampled) |
| Input Type | Differential |
| Sampling Rate | 1.5 Msps |
| Supply Voltage | 3 V (single supply) |
| Supply Current | 5.5 mA |
| Sleep Mode Power | 12 uW |
| Package | 32-pin QFN (5mm x 5mm) |
| Operating Temperature Range | 0C to +70C (commercial) |
| Screening Level | Commercial |
| Architecture | SAR (successive approximation) |
| Data Interface | Serial / SPI-compatible |
| Shutdown Mode | Yes (sleep mode) |
| RoHS Status | Compliant (PBF suffix) |
| Lead-Free | Yes |
LTC2351CUH-14 Pin Configuration
| Pin 1 | AIN0+ — Differential analog input channel 0, positive |
| Pin 2 | AIN0- — Differential analog input channel 0, negative |
| Pin 3 | AIN1+ — Differential analog input channel 1, positive |
| Pin 4 | AIN1- — Differential analog input channel 1, negative |
| Pin 5 | AIN2+ — Differential analog input channel 2, positive |
| Pin 6 | AIN2- — Differential analog input channel 2, negative |
| Pin 7 | AIN3+ — Differential analog input channel 3, positive |
| Pin 8 | AIN3- — Differential analog input channel 3, negative |
| Pin 9 | AIN4+ — Differential analog input channel 4, positive |
| Pin 10 | AIN4- — Differential analog input channel 4, negative |
| Pin 11 | AIN5+ — Differential analog input channel 5, positive |
| Pin 12 | AIN5- — Differential analog input channel 5, negative |
| Pin 13 | GND — Analog ground |
| Pin 14 | REF — Reference voltage bypass |
| Pin 15 | VREF — Reference voltage input |
| Pin 16 | VDD — Analog 3V supply |
| Pin 17 | OVDD — Digital I/O supply |
| Pin 18 | OGND — Digital ground |
| Pin 19 | CONVST — Conversion start input |
| Pin 20 | CS — Chip select, active low |
| Pin 21 | SCK — Serial clock input |
| Pin 22 | SDO — Serial data output |
| Pin 23 | BUSY — Conversion busy output |
| Pin 24 | SHDN — Shutdown input, active low |
| Pin 25 | NC — Not connected (per datasheet) |
| 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) |
| Pin 33 | EP — Exposed pad - thermal/ground, must be soldered to analog ground plane |
Typical Applications
LTC2351CUH-14 is suitable for 6 applications: Three-Phase Power Quality Monitoring, Multi-Axis Industrial Vibration Analysis, Portable Medical Instrumentation, Multi-Channel Data Acquisition Systems, Phased-Array Ultrasound Receivers, Multi-Sensor Industrial IoT Hubs.
Three-Phase Power Quality Monitoring
The LTC2351CUH-14's six simultaneously-sampled differential inputs directly accept the three phase voltages and three phase currents of a three-phase power line, eliminating the multiplexer skew that would otherwise corrupt harmonic measurement. At 1.5Msps per channel, the ADC captures harmonics well beyond the 50th harmonic of 50/60Hz mains, supporting Class 0.1 / 0.2 revenue-grade metering accuracy. With 5.5mA supply current at 3V and 12uW sleep current, it also fits compact energy-monitoring modules deployed behind smart meters.
Recommended
Multi-Axis Industrial Vibration Analysis
Six simultaneously-sampled channels make the LTC2351CUH-14 ideal for capturing vibration from three orthogonal accelerometers on a rotating machine (one per axis x 2 sensors). The 14-bit resolution and 1.5Msps per-channel throughput capture bearing-fault signatures up to 750kHz, while simultaneous sampling preserves phase relationships essential for FFT-based modal and order-tracking analysis. The 5x5mm QFN footprint enables high-density sensor clusters on condition-monitoring PCBs.
Recommended
Portable Medical Instrumentation
Battery-powered patient monitors and diagnostic equipment benefit from the LTC2351CUH-14's 5.5mA active supply current and 12uW sleep shutdown. Six differential inputs accept ECG, EEG, EMG, pulse-oximeter, temperature, and respiration channels simultaneously, preserving inter-channel phase for arrhythmia detection. The 32-lead 5x5mm QFN package plus 3V single-supply operation simplify FDA-compliant medical device design with extended battery runtime between charges.
Recommended
Multi-Channel Data Acquisition Systems
Simultaneous sampling is critical for phased-array ultrasound, sonar, and radar receivers where beamforming requires sub-sample phase accuracy across channels. The LTC2351CUH-14 delivers 1.5Msps per channel across six inputs, enabling 16-element equivalent phased arrays using three stacked ADCs. The compact 5x5mm QFN also permits dense PCB layouts in compact AFE daughter cards for medical imaging and defense applications.
Recommended
Phased-Array Ultrasound Receivers
Ultrasound transducers consist of 16 to 192 piezo elements that must be sampled with tight inter-channel phase coherence. Three LTC2351CUH-14 devices sample 18 channels simultaneously at 40MSps aggregate throughput, providing the raw data for digital beamforming in compact portable ultrasound carts. The 14-bit dynamic range and 5.5mA per-device supply current keep power consumption manageable in battery-powered point-of-care probes.
Recommended
Multi-Sensor Industrial IoT Hubs
Industrial IoT edge gateways aggregate data from strain gauges, pressure transducers, thermocouples, and load cells - all of which produce differential signals. The LTC2351CUH-14's six simultaneous inputs interface directly to these sensors after instrumentation-amp conditioning, while 12uW sleep power supports energy-harvested or battery-powered nodes that wake periodically to capture a synchronized burst of measurements across all sensors.
Recommended
Recommended Products Summary
Engineering reference data for LTC2351CUH-14 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LTC2351IUH-14#PBF | LTC2351CUH-14#TRPBF | LTC2351IUH-14#TRPBF | LTC2351CUK-14#PBF |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices (same brand) | Analog Devices (same brand) | Analog Devices (same brand) | Analog Devices (same brand) |
| Package | QFN-32 (5x5mm) | QFN-32 (5x5mm) - same | QFN-32 (5x5mm) - same | QFN-32 (5x5mm) - same | QFN-32 (5x5mm) - same |
| Resolution | 14 bit | 14 bit | 14 bit | 14 bit | 14 bit |
| Sampling Rate | 1.5 Msps | 1.5 Msps | 1.5 Msps | 1.5 Msps | 1.5 Msps |
| Number of Channels | 6 simultaneous | 6 simultaneous | 6 simultaneous | 6 simultaneous | 6 simultaneous |
| Operating Temperature | 0C to +70C | -40C to +85C | 0C to +70C | -40C to +85C | 0C to +70C |
| Supply Voltage | 3 V single supply | 3 V single supply | 3 V single supply | 3 V single supply | 3 V single supply |
| Supply Current | 5.5 mA | 5.5 mA | 5.5 mA | 5.5 mA | 5.5 mA |
| Sleep Mode Power | 12 uW | 12 uW | 12 uW | 12 uW | 12 uW |
Key Differentiators
- Industrial temperature option in identical footprint (vs LTC2351IUH-14#PBF)
- Tape-and-reel packaging for high-volume assembly (vs LTC2351CUH-14#TRPBF)
- 6-channel simultaneous sampling eliminates inter-channel skew (vs Multiplexed ADC alternatives)
Design Notes
Power the LTC2351CUH-14 from a clean, low-noise LDO such as the LT1761-3.3 placed within 5mm of the VDD pin. Add a 10uF ceramic (X7R) + 0.1uF X7R decoupling pair directly on VDD and OVDD. Reference noise on the analog supply directly degrades SNR, so avoid sharing the ADC supply rail with switching converters or digital logic that injects high-frequency switching noise.
Estimated: the QFN-32 (5x5mm) package with exposed pad (EP) has a typical theta_JA of approximately 40 C/W on a 4-layer JEDEC test board. At 3V supply and 5.5mA active current, the part dissipates about 16.5mW continuously, resulting in a negligible 0.7C temperature rise - no heatsink is required. Ensure the exposed pad is soldered to a continuous analog ground plane with at least 8 thermal vias to maximize heat spreading and low-impedance ground return.
Route the six differential input pairs as tightly-coupled 50-ohm microstrip or stripline pairs with matched lengths within each pair. Keep analog input traces on the top layer above a continuous ground plane; avoid routing input traces near digital signals, switching regulators, or the serial SCK/SDO lines. Place a 100-ohm differential RC anti-alias filter (1nF / 100-ohm / 1nF) on each input pair close to the ADC for best harmonic performance.
Do not omit the external reference bypass capacitor on the REF/VREF pin - the datasheet specifies a 10uF X7R cap with ESR less than 1 ohm for stability. Avoid driving the differential inputs outside the common-mode range specified in the datasheet; this can permanently damage the sample-and-hold ESD structures. Ensure the CONVST pulse meets the minimum pulse-width timing specification, otherwise the simultaneous-sampling guarantee is lost.
Compliance Information
RoHS compliant per #PBF suffix on distributor listings. Lead-free QFN package. Not AEC-Q100 qualified (industrial-grade commercial-temperature ADC); AEC-Q100 not typically applicable to commercial multi-channel ADCs.
