Analog Devices Inc. LTC1864LCS8#PBF

Overview

LTC1864LCS8#PBF from Analog Devices (formerly Linear Technology) is a 16-bit, 150ksps successive approximation ADC with true differential analog input, single 3V supply operation, and auto-shutdown power management. It features 450µA typical supply current at full speed, 82dB SNR, ±8LSB INL, and operates in an 8-lead MSOP package. It is used in high-precision, low-power data acquisition systems requiring rail-to-rail input capability and external reference flexibility.

For engineers reviewing the LTC1864LCS8#PBF datasheet, LTC1864LCS8#PBF pinout, LTC1864LCS8#PBF application, or LTC1864LCS8#PBF equivalent, key selection criteria include its differential input architecture, 150ksps sampling rate at sub-0.5mA, SPI/MICROWIRE-compatible serial interface, MSOP-8 footprint, and support for external references down to 1V full-scale - critical for battery-powered instrumentation and isolated sensing.

Technical Context

The LTC1864LCS8#PBF implements a switched-capacitor SAR architecture with integrated sample-and-hold, enabling precise conversion without external components. Its differential input rejects common-mode noise, and the external VREF pin allows ratiometric or absolute measurement configurations.

Conversion is initiated by a rising edge on CONV; after t_CONV ≈ 4.66µs, data becomes available on SDO synchronized to SCK falling edges. Auto-shutdown reduces current to 10µA at 1ksps, and the device supports no minimum data transfer rate - enabling flexible host timing.

Key Specifications

Pinout & Package

Package: 8-lead MSOP (MS8), 3.0mm × 3.0mm × 0.86mm body, 0.65mm pitch, exposed pad not present. RoHS-compliant, Pb-free, halogen-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with AD7682BCPZ-RL7 and LTC2311-16IMS8#PBF, the LTC1864LCS8#PBF uniquely combines true differential input, 3V-only operation, ultra-low 450µA active current, and 1V–VCC reference flexibility - making it optimal for space- and power-constrained 3V systems where common-mode rejection is essential.

Availability

LTC1864LCS8#PBF is available at Aetrix Electronics and suitable for portable instrumentation, isolated data acquisition, and compact signal conditioning requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for LTC1864LCS8#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 acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for legacy Linear parts including the LTC1864L series.

The LTC1864L belongs to Linear's precision low-power SAR ADC family, designed specifically for high-resolution, battery-operated, and space-constrained measurement systems where differential input integrity and microamp-level active current are critical.

FAQ

What is the maximum sampling frequency of the LTC1864LCS8#PBF?

The LTC1864LCS8#PBF supports a maximum sampling frequency of 150ksps, with guaranteed performance across the full operating temperature range (0°C to 70°C for the 'C' grade). At this rate, conversion time is 4.66µs, and the device draws 450µA typical supply current. Lower sampling rates reduce current consumption via automatic shutdown - e.g., 10µA at 1ksps - without requiring software intervention.

Does the LTC1864LCS8#PBF support true differential input?

Yes, the LTC1864LCS8#PBF provides true differential analog input on pins IN+ and IN–, enabling common-mode noise rejection and accurate measurement of small differential signals. The transfer function is based on (IN+ – IN–), with zero code at 0V difference and full scale at VREF – 1LSB. This differs from pseudo-differential or single-ended architectures and is confirmed in the functional block diagram and transfer curve figures of the official datasheet.

Can the LTC1864LCS8#PBF operate with a 1V reference voltage?

Yes, the LTC1864LCS8#PBF supports external reference voltages from 1V up to VCC (max 3.6V), as explicitly specified in the "Reference Input Range" section of the datasheet. This allows direct interfacing with low-voltage precision references (e.g., LT1460ACS8-1.25) or sensor bridges without level-shifting, preserving SNR and reducing component count in low-power designs.

What package type is used for the LTC1864LCS8#PBF?

The LTC1864LCS8#PBF uses the 8-lead MSOP (MS8) package - a 3.0mm × 3.0mm surface-mount outline with 0.65mm lead pitch. This is distinct from the SO-8 variant (LTC1864LCS8) and the 10-lead MSOP version. The MS8 package is documented in LTC drawing #05-08-1660 and is RoHS-compliant with Pb-free terminations.

How does the CONV pin control power states in the LTC1864LCS8#PBF?

The CONV pin serves dual functions: a rising edge initiates conversion, and holding CONV high after conversion completion places the LTC1864LCS8#PBF into auto-shutdown mode, reducing supply current to ~10µA. When CONV falls, SDO is enabled and data is clocked out via SCK. This hardware-controlled power sequencing eliminates the need for register writes or complex timing sequences - simplifying firmware and improving reliability in low-duty-cycle applications.