Analog Devices Inc. LTC2378HMS-18#PBF

Overview

LTC2378HMS-18#PBF from Analog Devices (formerly Linear Technology) is an 18-bit, 1 Msps successive approximation register (SAR) analog-to-digital converter with ±1.75 LSB INL max, 102 dB SNR at 2 kHz, fully differential ±V_REF input (2.5 V to 5.1 V), and digital gain compression (DGC) for single-supply amplifier interfacing. It operates from a 2.5 V analog supply and supports 1.8 V–5 V I/O logic, targeting high-precision data acquisition in medical imaging and industrial process control.

For engineers reviewing the LTC2378HMS-18#PBF datasheet, LTC2378HMS-18#PBF pinout, LTC2378HMS-18#PBF application, or LTC2378HMS-18#PBF equivalent, key selection criteria include guaranteed 18-bit no-missing-codes operation over –40°C to +125°C, internal conversion clock eliminating external timing constraints, daisy-chain SPI interface, and DGC-enabled 0.5 V to 4.5 V input range with 5 V reference.

Technical Context

The LTC2378HMS-18#PBF implements a charge redistribution capacitor DAC architecture with differential comparator and 18-bit successive approximation logic. Its conversion timing is governed by an internal oscillator (t_CONV = 460–527 ns), delivering true 1 Msps throughput with zero cycle latency and no pipeline delay.

It features dual power domains: 2.5 V V_DD for analog core and programmable 1.71 V–5.25 V O_VDD for digital I/O. The REF/DGC pin selects between full ±V_REF range (REF tied high) or DGC-compressed 0.1×V_REF to 0.9×V_REF range (REF/DGC tied low), enabling single-supply driver operation without resolution loss.

Key Specifications

Pinout & Package

Package: 16-lead plastic MSOP (5.0 mm × 4.4 mm), exposed pad not present (unlike DFN variant). Rated for –40°C to +125°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8860IDRCT and AD7960BCPZ-RL7, the LTC2378HMS-18#PBF uniquely combines 18-bit no-missing-codes assurance at 125°C, on-chip DGC for simplified analog front-end design, and SPI daisy-chain capability-making it optimal for space-constrained, thermally demanding, and multi-channel precision DAQ systems.

Availability

LTC2378HMS-18#PBF is available at Aetrix Electronics and suitable for medical imaging, high-speed industrial data acquisition, and extended-temperature industrial control requiring stable component supply and long-term lifecycle support.

Supply support for LTC2378HMS-18#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 LTC2378HMS-18#PBF belongs to ADI's legacy Linear Technology precision SAR ADC product line, engineered for applications demanding ultra-low noise, guaranteed monotonicity, and robust operation across extreme temperatures without performance degradation.

FAQ

What is the maximum operating temperature specification for the LTC2378HMS-18#PBF?

The LTC2378HMS-18#PBF is rated for operation from –40°C to +125°C, meeting the H-grade qualification standard. This is confirmed in the Absolute Maximum Ratings table and Electrical Characteristics section, where parameters like INL, SNR, and THD are explicitly specified "(H-Grade)" across the full –40°C to +125°C range. The MSOP package's θ_JA is 110°C/W, supporting reliable thermal performance in sealed enclosures.

Does the LTC2378HMS-18#PBF require an external clock source for conversion timing?

No, the LTC2378HMS-18#PBF does not require an external clock. It integrates an internal oscillator that sets the conversion time (t_CONV = 460–527 ns), eliminating external timing dependencies. The CNV pin serves solely as a start-of-conversion trigger; all timing-including acquisition window and serial data transfer-is derived from this internal clock, easing PCB layout and system synchronization.

How does Digital Gain Compression (DGC) function in the LTC2378HMS-18#PBF, and what is its practical benefit?

Digital Gain Compression (DGC) in the LTC2378HMS-18#PBF is enabled by grounding the REF/DGC pin, which digitally remaps the full-scale input range from ±V_REF to 0.1×V_REF to 0.9×V_REF. With a 5 V reference, this yields a 0.5 V to 4.5 V input span. This allows driving amplifiers (e.g., LT6350) to operate from a single 5.5 V supply instead of dual ±5 V rails-reducing system power, board area, and cost while preserving all 18 bits of resolution.

What are the supported logic voltage levels for the digital interface of the LTC2378HMS-18#PBF?

The LTC2378HMS-18#PBF supports 1.8 V, 2.5 V, 3.3 V, and 5 V logic levels on its digital interface. This is achieved via the independent O_VDD supply pin (1.71 V–5.25 V), which defines VIH (≥0.8×O_VDD) and VIL (≤0.2×O_VDD). All digital pins (SCK, SDO, RDL/SDI, BUSY, CHAIN, CNV) are compatible with these voltages, enabling direct interfacing with FPGAs, microcontrollers, and ASICs across diverse voltage domains without level shifters.

Is the LTC2378HMS-18#PBF pin-compatible with other variants in the LTC2378-18 family, such as the DFN-packaged versions?

No, the LTC2378HMS-18#PBF (16-lead MSOP) is not pin-compatible with the DFN-packaged variants (e.g., LTC2378CDE-18#PBF). While both share identical electrical functionality and pin functions, the MSOP package has a different lead count, pitch, and physical layout (e.g., exposed pad on DFN Pin 17 is absent in MSOP). The datasheet explicitly lists separate package drawings and thermal characteristics (θ_JA = 110°C/W for MSOP vs. 40°C/W for DFN), confirming mechanical incompatibility.