Analog Devices Inc. LTC2368CDE-24#PBF

Overview

LTC2368CDE-24#PBF from Analog Devices (formerly Linear Technology) is a 24-bit, 1 Msps pseudo-differential unipolar successive approximation register (SAR) ADC with integrated real-time digital averaging filter. It operates from a single 2.5V supply, accepts 0V to VREF input (VREF = 2.5V–5.1V), delivers ±4.5 ppm INL max, 98 dB SNR at 1 Msps, and achieves 140 dB dynamic range at 15.25 sps - ideal for high-precision seismic data acquisition systems requiring ultra-low noise and guaranteed no missing codes.

For engineers reviewing the LTC2368CDE-24#PBF datasheet, LTC2368CDE-24#PBF pinout, LTC2368CDE-24#PBF application, or LTC2368CDE-24#PBF equivalent, key selection criteria include its 24-bit resolution with ±0.5 ppm typical INL, integrated averaging (N = 1–65536), SPI-compatible 1.8V–5V I/O, daisy-chain capability, and DFN-16 (4 mm × 3 mm) package with exposed ground pad.

Technical Context

The LTC2368CDE-24#PBF implements a charge-redistribution SAR architecture with a built-in digital averaging filter that operates without configuration registers or external programming. Its pseudo-differential input stage uses IN+ and IN– with ±100 mV common-mode tolerance on IN–, enabling remote ground sensing while rejecting common-mode interference up to 83 dB at 500 kHz.

Conversion timing is triggered by a rising edge on CNV; BUSY goes high during conversion (615–675 ns) and returns low upon completion. The SPI interface supports MSB-first output, daisy-chain mode via CHAIN/RDL/SDI, and logic-level compatibility across 1.8V, 2.5V, 3.3V, and 5V OVDD - with SCK periods down to 10 ns (100 MHz max).

Key Specifications

Pinout & Package

The LTC2368CDE-24#PBF is housed in a 16-lead (4 mm × 3 mm) plastic DFN package with exposed thermal pad (Pin 17) that must be soldered to PCB ground for thermal and electrical performance. Pin count and layout match the MSOP variant but with reduced footprint and improved θ_JA (40°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution SAR ADC applications.

Compared with ADS1286IRGET and AD7616BSTZ, the LTC2368CDE-24#PBF uniquely combines 24-bit resolution, 1 Msps throughput, integrated averaging, and pseudo-differential architecture - delivering highest effective resolution per pin in compact DFN packaging without external configuration.

Availability

LTC2368CDE-24#PBF is available at Aetrix Electronics and suitable for seismology data acquisition, energy exploration sensors, medical imaging front-ends, high-speed industrial ATE, and precision industrial process control requiring stable component supply and long-term manufacturability.

Supply support for LTC2368CDE-24#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 LTC2368CDE-24#PBF belongs to ADI's legacy Linear Technology precision data converter portfolio, engineered specifically for applications demanding ultra-low noise, guaranteed 24-bit linearity, and minimal system-level integration effort in high-reliability instrumentation.

FAQ

What is the operating temperature range for the LTC2368CDE-24#PBF?

The LTC2368CDE-24#PBF is specified for operation from 0°C to 70°C (Commercial grade). This range is confirmed in the ORDER INFORMATION table and applies to all electrical specifications unless otherwise noted. The device maintains ±4.5 ppm INL max and 98 dB SNR across this full range, making it suitable for laboratory instruments and non-automotive industrial environments.

Does the LTC2368CDE-24#PBF require external configuration registers or firmware setup?

No, the LTC2368CDE-24#PBF does not require external configuration registers or firmware initialization. Its integrated digital averaging filter operates automatically based on the number of averages selected via hardware pins or SPI command - no register writes are needed. All timing, interface mode (normal vs. daisy-chain), and power-down behavior are controlled by dedicated pins (CHAIN, CNV, RDL/SDI), simplifying system integration.

How does the pseudo-differential input architecture of the LTC2368CDE-24#PBF improve measurement accuracy?

The LTC2368CDE-24#PBF uses IN+ and IN– inputs where IN– serves as a remote ground sense point with ±100 mV tolerance. This configuration rejects common-mode noise up to 83 dB at 500 kHz while preserving differential signal integrity. In practice, this enables accurate digitization in electrically noisy settings - such as near motor drives or switching regulators - without requiring matched external resistor networks or instrumentation amplifiers.

What is the purpose of the exposed pad (Pin 17) on the LTC2368CDE-24#PBF DFN package?

The exposed pad (Pin 17) on the LTC2368CDE-24#PBF is electrically connected to GND and must be soldered directly to the PCB ground plane. It provides both thermal dissipation (θ_JA = 40°C/W) and low-impedance grounding for analog and digital sections, reducing noise coupling and improving PSRR. Failure to solder this pad compromises INL performance, SNR, and thermal reliability - especially at full 1 Msps operation.

Can the LTC2368CDE-24#PBF interface directly with a 1.8V microcontroller SPI port?

Yes, the LTC2368CDE-24#PBF supports 1.8V logic levels via its OVDD pin. When OVDD = 1.8V, all digital inputs (CNV, SCK, CHAIN, RDL/SDI) recognize 0.2×OVDD (0.36V) as logic low and 0.8×OVDD (1.44V) as logic high, while SDO outputs are compatible with 1.8V receivers. This eliminates level-shifting circuitry and simplifies interfacing with modern ultra-low-voltage MCUs in portable instrumentation.