Analog Devices Inc. LTC2321CUFD-12#PBF

Overview

LTC2321CUFD-12#PBF from Analog Devices is a dual-channel, 12-bit + sign successive approximation register (SAR) ADC with differential inputs, 2 Msps per channel throughput, ±0.5 LSB typical INL, 73 dB SNR at 500 kHz, and integrated 2.048 V / 4.096 V temperature-compensated reference. It operates from single 3.3 V or 5 V supply and supports CMOS or LVDS serial interface - ideal for high-speed data acquisition in motor control and optical networking.

For engineers reviewing the LTC2321CUFD-12#PBF datasheet, LTC2321CUFD-12#PBF pinout, LTC2321CUFD-12#PBF application, or LTC2321CUFD-12#PBF equivalent, key selection criteria include guaranteed 12-bit no-missing-codes performance, wide input common mode range (0 V to VDD), zero-cycle latency, low power dissipation (30 mW/ch typical), and operation across 0°C to 70°C ambient.

Technical Context

The LTC2321CUFD-12#PBF implements two independent SAR ADC cores with shared reference and clock resources, enabling simultaneous sampling and conversion on both channels. Its differential input stage supports fully differential, pseudo-differential bipolar, and pseudo-differential unipolar configurations without external configuration - all within a single 28-lead QFN package.

It features an onboard low-drift (≤20 ppm/°C) reference buffer delivering either 2.048 V or 4.096 V, configurable via REFINT pin. The SPI-compatible serial interface supports both CMOS (1.8 V–2.5 V I/O) and LVDS modes, with skew-matched CLKOUT output for deterministic timing at FPGA/DSP receivers.

Key Specifications

Pinout & Package

Package: 28-lead (4 mm × 5 mm) plastic QFN (UFD), exposed pad (Pin 29) required to be soldered to PCB ground plane for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel SAR ADC applications.

Compared with ADS8860IDRCT and AD7961BCPZ, the LTC2321CUFD-12#PBF uniquely balances dual-channel 2 Msps throughput, integrated reference, wide common mode input, and dual-mode I/O - reducing total system component count and layout complexity for mid-speed industrial DAQ and motor control.

Availability

LTC2321CUFD-12#PBF is available at Aetrix Electronics and suitable for high-speed data acquisition systems, optical network monitoring equipment, and industrial motor control designs requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for LTC2321CUFD-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 (now part of Analog Devices, Inc.) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC2321CUFD-12#PBF belongs to the Linear Technology LTC23xx family of high-speed SAR ADCs, designed specifically for applications demanding low latency, excellent AC performance, and robust operation in electrically noisy environments.

FAQ

What is the maximum sampling rate supported by the LTC2321CUFD-12#PBF?

The LTC2321CUFD-12#PBF supports a maximum sampling rate of 2 Msps per channel, with guaranteed timing parameters including tCONV ≤ 220 ns and tCYC ≥ 500 ns. This enables real-time capture of signals with up to 10 MHz –3dB input bandwidth while maintaining 73 dB SNR at 500 kHz input frequency.

Does the LTC2321CUFD-12#PBF require an external reference voltage?

No - the LTC2321CUFD-12#PBF integrates a low-drift (≤20 ppm/°C) 2.048 V / 4.096 V temperature-compensated reference buffer. REFOUT1 and REFOUT2 pins deliver this reference; grounding REFINT disables the buffers, allowing external reference injection in the 1.25 V to 5 V range.

Can the LTC2321CUFD-12#PBF interface directly with a 1.8 V FPGA I/O bank?

Yes - the LTC2321CUFD-12#PBF supports 1.8 V to 2.5 V OVDD, enabling direct CMOS-level interfacing with 1.8 V FPGA I/O banks. In LVDS mode, it operates at 2.5 V OVDD and delivers compliant differential output voltage (100–300 mV) with proper 100 Ω termination.

How does the LTC2321CUFD-12#PBF handle pseudo-differential unipolar inputs?

The LTC2321CUFD-12#PBF accepts pseudo-differential unipolar inputs (e.g., AIN1+ = signal, AIN1– = GND) without configuration. It digitizes the 0 V to REFOUT range into 0x0000–0x0FFF codes (12-bit unipolar span), preserving overrange detection capability and leveraging its full 0 V to VDD common mode range.

What power-saving modes does the LTC2321CUFD-12#PBF offer?

The LTC2321CUFD-12#PBF provides Nap mode (2.55 mA typical IVDD + IOVDD) and Sleep mode (1 µA typical IVDD + IOVDD), both entered via CNV timing control. These modes reduce power during idle periods while retaining fast wake-up (<10 ms REFOUT stabilization) and full functionality upon resumption.