LTC2351CUH-14#PBF - 14-Bit 1.5Msps 6-Ch Simultaneous-Sampling ADC | ADI
MPN: LTC2351CUH-14#PBF ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $16.5 | $16.50 |
| 10 | $14.85 | $148.50 |
| 100 | $12.4 | $1,240.00 |
| 500 | $10.65 | $5,325.00 |
| 1,000 | $9.4 | $9,400.00 |
LTC2351CUH-14#PBF Overview
A SAR (Successive Approximation Register) ADC is a type of data converter that converts an analog input into a digital code by iteratively comparing the input against a precision DAC and a reference voltage. In system hierarchy, the LTC2351-14 belongs to: SAR ADC -> ADC -> data converter -> signal chain IC -> analog/mixed-signal semiconductor. SAR ADCs are valued for their deterministic latency, lack of pipeline delay, and excellent DC accuracy, which makes the simultaneous-sampling variant especially useful when the relative phase between channels must be preserved (such as in three-phase power metering or vibration analysis).
Key features include six differential inputs sampled on the same clock edge (preserving inter-channel phase), a serial LVCMOS-compatible interface, an internal 2.5 V reference (with provision for an external reference), and an input common-mode range that accommodates both unipolar and bipolar signals when paired with appropriate driver circuits. The 32-lead QFN package provides a low thermal-resistance path and a compact 5 mm x 5 mm footprint suitable for space-constrained PCB designs.
Typical applications include multiphase power monitoring, industrial process control and instrumentation, portable and handheld test gear, simultaneous data acquisition systems, vibration and modal analysis, and motor control feedback. The wide input common-mode range and differential architecture also simplify connection to bridge sensors and current-shunt monitors.
A practical design tip is to place 0.1 uF ceramic bypass capacitors close to each supply pin and to keep the analog input traces short and symmetric, because aperture-time mismatch between channels at 1.5 Msps can otherwise manifest as inter-channel skew that degrades phase-sensitive measurements.
This page synthesizes distributor pricing, drop-in alternatives, and design notes not found in the manufacturer datasheet, giving engineers a single source for evaluating, sourcing, and laying out the LTC2351CUH-14#PBF.
Drop-in alternatives for LTC2351CUH-14#PBF — 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#PBF (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:
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)
LTC2351CUH-14
✅ Drop-In✓ In Stock
$12.4 / Unit
View Datasheet →LTC2351CUH-14#PBF-ND
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2351CUH-14#PBF Maximum Ratings & Electrical Characteristics
| Resolution | 14 bits |
| Number of Input Channels | 6 differential (simultaneously sampled) |
| Sampling Rate | 1.5 Msps |
| Architecture | SAR (Successive Approximation Register) |
| Input Type | Differential |
| Supply Voltage | 3 V (single supply) |
| Supply Current (active) | 5.5 mA |
| Sleep Mode Current | 12 uW |
| Internal Reference | 2.5 V (external reference supported) |
| Data Interface | Serial LVCMOS-compatible |
| Package | 32-pin QFN (5 mm x 5 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0C to +70C (commercial grade) |
| Lead Free / RoHS | Lead free (PBF suffix), RoHS compliant |
| Throughput per Channel | 1.5 Msps / 6 channels (sequential conversion of sampled inputs) |
LTC2351CUH-14#PBF Pin Configuration
| Pin 1 | GND — Analog ground |
| Pin 2 | IN0+ — Differential analog input 0, positive |
| Pin 3 | IN0- — Differential analog input 0, negative |
| Pin 4 | IN1+ — Differential analog input 1, positive |
| Pin 5 | IN1- — Differential analog input 1, negative |
| Pin 6 | IN2+ — Differential analog input 2, positive |
| Pin 7 | IN2- — Differential analog input 2, negative |
| Pin 8 | IN3+ — Differential analog input 3, positive |
| Pin 9 | IN3- — Differential analog input 3, negative |
| Pin 10 | GND — Analog ground |
| Pin 11 | VREF — Reference voltage (2.5 V internal, or external reference input) |
| Pin 12 | REFCOMP — Reference bypass / compensation pin |
| Pin 13 | REFBUF — Internal reference buffer output |
| Pin 14 | GND — Analog ground |
| Pin 15 | IN4+ — Differential analog input 4, positive |
| Pin 16 | IN4- — Differential analog input 4, negative |
| Pin 17 | IN5+ — Differential analog input 5, positive |
| Pin 18 | IN5- — Differential analog input 5, negative |
| Pin 19 | GND — Analog ground |
| Pin 20 | SLEEP — Sleep mode control (active high) |
| Pin 21 | CONV — Convert start input |
| Pin 22 | CLK — Serial clock input |
| Pin 23 | SDOA — Serial data output A (channels 0-2) |
| Pin 24 | SDOB — Serial data output B (channels 3-5) |
| Pin 25 | OVDD — Digital interface supply voltage |
| Pin 26 | OGND — Digital interface ground |
| Pin 27 | NC — Not connected (per datasheet) |
| Pin 28 | NC — Not connected (per datasheet) |
| Pin 29 | VDD — Analog supply voltage (3 V) |
| Pin 30 | VDD — Analog supply voltage (3 V) |
| Pin 31 | GND — Analog ground |
| Pin 32 | GND — Analog ground |
Typical Applications
LTC2351CUH-14#PBF is suitable for 6 applications: Three-Phase Power Monitoring, Industrial Process Control & PLC Analog Input Modules, Portable / Handheld Data Acquisition, Vibration & Modal Analysis, Motor Control Feedback Loops, Multichannel Instrumentation & Test Equipment.
Three-Phase Power Monitoring
The LTC2351CUH-14#PBF's six simultaneously-sampled differential inputs and 1.5 Msps throughput make it an ideal ADC for three-phase voltage and current monitoring in power meters and motor drives. All three phase channels are captured on the same convert edge, preserving the relative phase angle between currents and voltages which is critical for accurate real-power, reactive-power, and power-factor calculations. Per the datasheet, the differential inputs accept the output of current transformers or shunt amplifiers directly. The 12 uW sleep current allows battery-backed smart meters to spend most of their time in standby while still supporting on-demand high-speed sampling for transient capture.
Recommended
Industrial Process Control & PLC Analog Input Modules
With six differential inputs and 1.5 Msps aggregate throughput, the LTC2351CUH-14#PBF lets a single ADC service multiple 4-20 mA or voltage-loop channels on a PLC analog input card. The differential inputs reject common-mode noise from long industrial cabling and ground loops, while the 14-bit resolution provides sufficient dynamic range for process variables such as pressure, temperature, and flow. The 32-pin 5x5 mm QFN package supports compact module layouts where each millimeter of PCB area matters. Designers should pair the ADC with instrumentation amplifiers for higher-impedance sensors and place 0.1 uF bypass capacitors close to each supply pin.
Recommended
Portable / Handheld Data Acquisition
The LTC2351CUH-14#PBF's 5.5 mA active supply current and 12 uW sleep-mode power make it a strong fit for battery-powered portable data loggers and handheld oscilloscope front-ends. With six differential channels available, a single instrument can monitor multiple sensors simultaneously without requiring a multiplexer, preserving phase relationships in vibration or acoustic capture. The serial LVCMOS interface minimizes pin count and enables connection to small microcontrollers such as the LPC11C14FBD48 or LPC1517JBD64E for portable designs. The QFN package's small 5x5 mm footprint is well-suited to compact handheld enclosures.
Recommended
Vibration & Modal Analysis
Simultaneous sampling on all six channels makes the LTC2351CUH-14#PBF well-suited to multi-axis accelerometer systems used in vibration monitoring and modal analysis. Because every channel is captured on the same convert edge, the relative phase between axes (X/Y/Z plus reference points) is preserved, which is essential for computing transfer functions and identifying structural resonances. The 1.5 Msps aggregate rate supports vibration analysis up to the audio band with comfortable margin. Designers typically pair the ADC with IEPE-compatible front ends for accelerometer excitation and biasing.
Recommended
Motor Control Feedback Loops
The LTC2351CUH-14#PBF's six differential inputs and 1.5 Msps throughput provide ample bandwidth for sampling the three phase currents and three phase voltages in a field-oriented control (FOC) loop for BLDC or PMSM motors. Differential sampling rejects the large common-mode dv/dt transients produced by the inverter stage. The fast SAR architecture delivers deterministic conversion latency, simplifying the control loop timing. The exposed-pad QFN package provides the thermal headroom needed when sampling inverter-class voltages with the appropriate resistive dividers.
Recommended
Multichannel Instrumentation & Test Equipment
Bench-top instrumentation such as multi-channel oscilloscope front-ends, data recorders, and automated test equipment benefits from the LTC2351CUH-14#PBF's six simultaneously-sampled differential inputs. With 14-bit resolution and 1.5 Msps aggregate throughput, the ADC can capture multi-channel waveforms with preserved phase relationships for analysis. The internal 2.5 V reference simplifies design while still allowing an external reference when calibration is required. The 32-pin QFN's exposed pad ensures low thermal drift and stable measurements across the 0C to +70C commercial temperature range.
Recommended
Recommended Products Summary
Engineering reference data for LTC2351CUH-14#PBF — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LTC2351IUH-14#PBF | LTC2351CUH-14#TRPBF | LTC2351IUH-14#TRPBF | LTC2351CUH-14 | LTC2351CUH-14#PBF-ND |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 32-pin QFN (5x5 mm) | 32-pin QFN (5x5 mm) - same | 32-pin QFN (5x5 mm) - same | 32-pin QFN (5x5 mm) - same | 32-pin QFN (5x5 mm) - same | 32-pin QFN (5x5 mm) - same |
| Resolution | 14-bit | 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 | 1.5 Msps |
| Number of Channels | 6 differential | 6 differential | 6 differential | 6 differential | 6 differential | 6 differential |
| Operating Temperature Range | 0C to +70C (commercial) | -40C to +85C (industrial) | 0C to +70C (commercial) | -40C to +85C (industrial) | 0C to +70C (commercial) | 0C to +70C (commercial) |
| Supply Voltage | 3 V single | 3 V single | 3 V single | 3 V single | 3 V single | 3 V single |
| Packaging Format | Tube (lead-free PBF) | Tube (lead-free PBF) | Tape & Reel (lead-free PBF) | Tape & Reel (lead-free PBF) | Tube (legacy non-PBF) | DigiKey catalog number, same as PBF |
Key Differentiators
- Six simultaneously-sampled differential channels in a single ADC (vs LTC2309CUF (12-channel single-ended mux'd SAR))
- Higher throughput (1.5 Msps) vs lower-channel alternatives (vs LTC2335ILX-16#PBF (16-bit, 500 ksps))
- Lower power with deep sleep shutdown mode (vs Generic 6-channel SAR ADCs without sleep mode)
Design Notes
Place 0.1 uF ceramic bypass capacitors as close as possible to each VDD and OVDD pin, and add a single 10 uF bulk capacitor near the supply entry point. The exposed thermal pad must be soldered to a continuous, low-impedance ground plane with multiple vias to the inner ground layer; this provides both thermal relief and a clean analog ground return. Per the LTC2351-14 datasheet, ground plane discontinuities under the analog inputs can introduce aperture-time mismatch that manifests as inter-channel skew at 1.5 Msps.
Estimated: With a 5.5 mA active supply current at 3 V, the LTC2351CUH-14#PBF dissipates approximately 16.5 mW during continuous conversion; for battery-powered designs, ensure the firmware uses the SLEEP pin to enter the 12 uW shutdown mode between sample bursts. Note also that the six differential inputs have a finite common-mode range - signals outside the input common-mode window must be shifted with input driver op-amps such as the LT1028 or LT1990 to avoid saturating the input sampling network.
Route analog input traces as differential pairs with matched lengths to preserve the simultaneous-sampling benefit; a length mismatch of just 1 cm introduces approximately 50 ps of skew, which at 1.5 Msps and a 100 kHz input can cause measurable inter-channel phase error. Keep digital interface traces (CLK, CONV, SDOA, SDOB) away from the analog inputs and reference pins, and consider a separate OGND island tied to GND at a single point near the exposed pad.
Compliance Information
RoHS compliant and lead-free indicated by the #PBF suffix per Analog Devices ordering convention. Not AEC-Q100 qualified (industrial-grade parts available as LTC2351IUH-14#PBF). Conflict-minerals and halogen-free status not explicitly stated in the verified web data; set to unknown.
