Analog Devices Inc. LTC2321HUFD-12#TRPBF

Overview

LTC2321HUFD-12#TRPBF from Analog Devices is a dual-channel, 12-bit + sign successive approximation register (SAR) analog-to-digital converter with differential inputs, 2 Msps per channel throughput, ±0.5 LSB typical INL, 73 dB SNR at 500 kHz, and operation up to 125°C. It integrates dual low-drift (20 ppm/°C max) internal references (2.048 V or 4.096 V), supports CMOS or LVDS serial I/O, and targets high-speed data acquisition in harsh environments.

For engineers reviewing the LTC2321HUFD-12#TRPBF datasheet, LTC2321HUFD-12#TRPBF pinout, LTC2321HUFD-12#TRPBF application, or LTC2321HUFD-12#TRPBF equivalent, key selection considerations include guaranteed 12-bit no-missing-codes performance across –40°C to 125°C, zero-cycle latency timing, differential input common mode range spanning 0 V to VDD, and flexible reference configuration (internal/external, 2.048 V/4.096 V).

Technical Context

The LTC2321HUFD-12#TRPBF implements two independent SAR ADC cores with shared clocking and serial interface logic. Each channel features a fully differential sample-and-hold with 10 pF input capacitance and 15 Ω switch on-resistance, enabling bipolar, pseudo-differential unipolar, and pseudo-differential bipolar input configurations without external hardware changes.

Its SPI-compatible serial interface operates in CMOS (1.8 V–2.5 V OVDD) or LVDS mode (100 Ω differential termination), delivering 13-bit two's complement output (12-bit + sign) with skew-matched CLKOUT for deterministic timing. Internal reference buffers are independently configurable via REFINT and support 1.25 V–5 V external reference injection when disabled.

Key Specifications

Pinout & Package

Package: 28-lead (4 mm × 5 mm) plastic QFN (UFD) with exposed pad (Pin 29) 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 AD7322BRUZ and ADS8862IDRCT, the LTC2321HUFD-12#TRPBF uniquely combines dual 2 Msps channels, –40°C to 125°C operation, LVDS/CMOS flexibility, and zero-cycle latency-making it the sole option for high-reliability, high-throughput embedded acquisition where timing determinism and thermal robustness are non-negotiable.

Availability

LTC2321HUFD-12#TRPBF is available at Aetrix Electronics and suitable for high-speed motor control, optical network monitoring, and automotive battery management requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC2321HUFD-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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC2321HUFD-12#TRPBF belongs to the Linear Technology high-speed precision SAR ADC product line, designed specifically for demanding data acquisition systems requiring simultaneous sampling, wide temperature operation, and minimal system-level calibration effort.

FAQ

What is the maximum operating temperature of the LTC2321HUFD-12#TRPBF?

The LTC2321HUFD-12#TRPBF is rated for continuous operation from –40°C to +125°C, meeting the H-grade specification. This makes it suitable for under-hood automotive applications, industrial motor drives, and downhole instrumentation where ambient temperatures exceed 105°C. Thermal performance is validated per JEDEC JESD51-2, with θ_JA = 43°C/W and exposed pad soldered to PCB ground.

Does the LTC2321HUFD-12#TRPBF support external reference inputs?

Yes, the LTC2321HUFD-12#TRPBF supports external reference inputs. By grounding the REFINT pin (Pin 28), both internal reference buffers (REFOUT1 and REFOUT2) are disabled, allowing external voltages from 1.25 V to 5 V to be applied directly to REFOUT1 and REFOUT2 pins. This enables system-level ratiometric measurement or use of ultra-low-noise external references.

How does the LTC2321HUFD-12#TRPBF achieve zero-cycle latency?

The LTC2321HUFD-12#TRPBF achieves zero-cycle latency by using a successive approximation architecture with no pipeline stages. Conversion completes within a single sampling period (500 ns at 2 Msps), and the result is immediately available on the SDO lines after the final SCK edge-eliminating the fixed delay inherent in pipelined or sigma-delta ADCs. This is essential for real-time closed-loop control.

Can the LTC2321HUFD-12#TRPBF interface with both CMOS and LVDS logic families?

Yes, the LTC2321HUFD-12#TRPBF supports both interfaces via the CMOS/LVDS pin (Pin 25). Grounding this pin selects CMOS mode (1.8 V–2.5 V OVDD, single-ended SDO/SCK); tying it to OVDD enables standard LVDS (100 Ω differential termination); leaving it floating activates low-power LVDS. The same physical pins serve both modes-no redesign needed.

What is the significance of the "+ sign" in the LTC2321HUFD-12#TRPBF's 12-bit + sign resolution?

The "+ sign" denotes that the LTC2321HUFD-12#TRPBF outputs a 13-bit two's complement code: 12 magnitude bits plus 1 sign bit. This allows seamless digitization of bipolar signals (e.g., ±2.048 V) without external level-shifting. The MSB indicates polarity, and the full 13-bit range (–4096 to +4095) maps to the differential input span of ±REFOUT, preserving dynamic range.