Analog Devices Inc. LTC2351CUH-12#PBF

Overview

LTC2351CUH-12#PBF from Analog Devices (formerly Linear Technology) is a 12-bit, 1.5 Msps simultaneous-sampling ADC with six differential input channels, 72 dB SINAD, 83 dB CMRR, and 250 ksps throughput per channel. It operates from a single 3 V supply, draws only 5.5 mA active current, and supports unipolar (0 V to 2.5 V) or bipolar (±1.25 V) differential inputs-ideal for multiphase power measurement and motor control systems requiring synchronized voltage/current acquisition.

For engineers reviewing the LTC2351CUH-12#PBF datasheet, LTC2351CUH-12#PBF pinout, LTC2351CUH-12#PBF application, or LTC2351CUH-12#PBF equivalent, key selection criteria include simultaneous sampling capability, rail-to-rail analog input swing compatibility, SPI-compatible serial interface timing, and thermal performance across 0°C to 70°C operation.

Technical Context

The LTC2351CUH-12#PBF integrates six independent sample-and-hold circuits triggered synchronously on the rising edge of CONV, enabling true simultaneous acquisition across all six differential pairs. Conversion proceeds at 250 ksps per channel using a 12-bit successive-approximation architecture with internal 2.5 V bandgap reference.

It features three power modes: Active (5.5 mA), Nap (1.5 mA), and Sleep (12 μW), controlled via CONV pulse sequences. Input range selection (unipolar/bipolar) is managed by the BIP pin, while channel count (1–6) is set by SEL2/SEL1/SEL0, with output data formatted in straight binary (unipolar) or 2's complement (bipolar).

Key Specifications

Pinout & Package

Package: 32-pin plastic QFN (5 mm × 5 mm), exposed pad (Pin 33) tied to GND for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar simultaneous-sampling ADC applications.

Compared with ADS8686SIRTVR and AD7606C-18, the LTC2351CUH-12#PBF delivers optimal balance of speed (1.5 Msps), power (5.5 mA), size (5 mm × 5 mm QFN), and simultaneous sampling fidelity for space- and energy-constrained industrial control systems.

Availability

LTC2351CUH-12#PBF is available at Aetrix Electronics and suitable for multiphase power measurement, motor control, and uninterruptible power supplies requiring stable component supply, long-term lifecycle support, and guaranteed authentic sourcing.

Supply support for LTC2351CUH-12#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 semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC2351CUH-12#PBF belongs to ADI's precision data acquisition portfolio, designed specifically for applications demanding synchronized multi-channel sampling, low power, and robust noise immunity in harsh electrical environments.

FAQ

What is the operating temperature range of the LTC2351CUH-12#PBF?

The LTC2351CUH-12#PBF is rated for 0°C to 70°C ambient operation, as indicated by the "C" grade in its part number. This commercial-grade specification ensures stability in office, laboratory, and non-extreme industrial environments where thermal management is moderate. The device maintains full parametric performance-including 72 dB SINAD and 83 dB CMRR-across this entire range when powered from a 3 V supply.

How does the LTC2351CUH-12#PBF achieve simultaneous sampling across six channels?

The LTC2351CUH-12#PBF achieves true simultaneous sampling using six independent sample-and-hold (S/H) circuits, each dedicated to one differential input pair (CH0–CH5). All six S/H units capture their respective analog inputs at the exact same instant-the rising edge of the CONV signal-eliminating inter-channel timing skew. This architecture ensures phase-coherent acquisition critical for vector-based calculations in power and motor control.

Can the LTC2351CUH-12#PBF use an external reference, and what are the voltage limits?

Yes, the LTC2351CUH-12#PBF supports external reference override via the VREF pin. An external reference between 2.55 V and VDD (max 3.6 V) can replace the internal 2.5 V bandgap reference. This allows users to improve absolute accuracy, reduce temperature drift, or align with system-level calibration standards-while maintaining full 12-bit linearity and specified dynamic performance.

What is the minimum acquisition time required before the next conversion starts?

The LTC2351CUH-12#PBF specifies a typical sample-and-hold acquisition time (tACQ) of 39 ns. This is the minimum time required after the 96th SCK rising edge for the internal capacitors to settle before the next CONV rising edge triggers a new simultaneous sample. Meeting this timing ensures full 12-bit accuracy and avoids missing-code errors during continuous high-speed operation.

How does the SEL2/SEL1/SEL0 pin configuration affect conversion throughput?

The SEL2/SEL1/SEL0 pins configure the number of channels converted per cycle: 000 = 1 channel (CH0 only), 001 = 2 channels (CH0–CH1), up to 101/110/111 = all 6 channels. Throughput scales inversely-e.g., converting only 3 channels reduces total conversion time from 96 to 48 SCK cycles, raising per-channel rate from 250 ksps to 500 ksps-enabling adaptive sampling based on real-time system needs.