Analog Devices Inc. LTC2351CUH-12#TRPBF

Overview

LTC2351CUH-12#TRPBF from Analog Devices (formerly Linear Technology) is a 12-bit, 1.5 Msps simultaneous-sampling analog-to-digital converter with six fully differential input channels, 72 dB SINAD, 83 dB common-mode rejection, and operation from a single 3 V supply. It delivers 250 ksps per channel throughput in a compact 32-pin QFN (5 mm × 5 mm), supporting portable and space-constrained data acquisition systems.

For engineers reviewing the LTC2351CUH-12#TRPBF datasheet, LTC2351CUH-12#TRPBF pinout, LTC2351CUH-12#TRPBF application, or LTC2351CUH-12#TRPBF equivalent, key selection considerations include simultaneous sampling integrity, rail-to-rail differential input flexibility (0 V–2.5 V unipolar or ±1.25 V bipolar), low-power shutdown modes (12 μW Sleep, 4.5 mW Nap), SPI-compatible serial interface timing, and channel-select configuration via SEL2/SEL1/SEL0.

Technical Context

The LTC2351CUH-12#TRPBF integrates six independent sample-and-hold circuits triggered synchronously on the rising edge of CONV, enabling true simultaneous capture across all six differential inputs. Conversion proceeds at 250 ksps per channel using a 12-bit successive-approximation architecture with internal 2.5 V bandgap reference (±15 ppm/°C tempco) or external reference override capability.

Its digital interface uses a 3-wire SPI-compatible protocol requiring up to 96 SCK cycles for full 6-channel readout, with MSB-first output on SDO. Channel count is dynamically configurable via SEL2/SEL1/SEL0 (000–111), and input polarity is selected by BIP pin state-output format shifts between straight binary (unipolar) and 2's complement (bipolar).

Key Specifications

Pinout & Package

Package: 32-pin plastic QFN (5 mm × 5 mm), exposed pad (Pin 33) soldered to PCB ground for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7656ASTZ and LTC2358IUK-12#PBF, the LTC2351CUH-12#TRPBF offers optimal balance of 12-bit precision, ultra-low power (16.5 mW), compact 32-pin QFN packaging, and true 3 V single-supply operation-making it ideal for portable, thermally sensitive, or cost-optimized simultaneous-sampling systems where 16-bit resolution is unnecessary.

Availability

LTC2351CUH-12#TRPBF is available at Aetrix Electronics and suitable for multiphase motor control, uninterruptible power supplies, and portable data acquisition systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant lead-free packaging.

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

The LTC2351CUH-12#TRPBF belongs to ADI's high-speed precision ADC product line, designed specifically for applications demanding synchronized multi-channel acquisition with low power, small size, and robust noise immunity-such as energy metering, motor drives, and portable test equipment.

FAQ

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

The LTC2351CUH-12#TRPBF 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 reliable performance in office, laboratory, and non-extreme industrial environments where thermal management is controlled. The device maintains full parametric compliance-including 72 dB SINAD and 83 dB CMRR-across this entire range when powered from a stable 3 V supply.

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

The LTC2351CUH-12#TRPBF 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 are triggered by the same rising edge of the CONV signal, capturing analog values at precisely the same instant. This architecture eliminates inter-channel aperture skew (specified at ≤200 ps), ensuring phase-coherent digitization essential for vector-based calculations in power and motor control.

Can the LTC2351CUH-12#TRPBF use an external reference, and what are the requirements?

Yes, the LTC2351CUH-12#TRPBF supports external reference override via the VREF pin. An external voltage between 2.55 V and VDD (max 3.6 V) can be applied to replace the internal 2.5 V bandgap reference. This allows improved absolute accuracy and lower drift when paired with a precision external reference IC. The internal reference remains disabled during external use, and the 10 μF bypass capacitor must still be connected from VREF to GND for stability.

What is the purpose of the SEL2/SEL1/SEL0 pins on the LTC2351CUH-12#TRPBF?

The SEL2/SEL1/SEL0 pins on the LTC2351CUH-12#TRPBF configure the number of active channels per conversion cycle-from 1 (000) to 6 (101/110/111). This binary encoding allows dynamic throughput scaling: selecting fewer channels increases per-channel sampling rate (e.g., 3 channels yield 500 ksps/ch). These pins must remain static during conversion and subsequent data readout to ensure deterministic timing and data alignment.

Does the LTC2351CUH-12#TRPBF support both unipolar and bipolar input ranges, and how is this selected?

Yes, the LTC2351CUH-12#TRPBF supports both 0 V–2.5 V unipolar and ±1.25 V bipolar differential input ranges. Selection is controlled by the BIP pin: LOW configures unipolar mode with straight-binary output coding; HIGH configures bipolar mode with 2's complement output. The BIP state must be held constant during conversion and readout; changing it between conversions requires full acquisition time (39 ns) before the next CONV pulse to ensure valid data.