Analog Devices Inc. LTC1864LIMS8#TRPBF

Overview

LTC1864LIMS8#TRPBF from Analog Devices (formerly Linear Technology) is a 16-bit, 150ksps successive approximation ADC with true differential analog input, single 3V supply operation, and MSOP-8 package. It features auto shutdown (450µA typical at full speed, dropping to 10µA at 1ksps), SPI/MICROWIRE-compatible 3-wire serial interface, and external reference pin supporting 1V to VCC full-scale spans - enabling direct connection to low-output-impedance sensors in portable instrumentation.

For engineers reviewing the LTC1864LIMS8#TRPBF datasheet, LTC1864LIMS8#TRPBF pinout, LTC1864LIMS8#TRPBF application, or LTC1864LIMS8#TRPBF equivalent, key selection criteria include its differential input architecture, guaranteed no missing codes over 14 bits, ±8 LSB INL, 82 dB SNR, and compatibility with ratiometric or precision external references - critical for high-resolution, low-power data acquisition where board space and battery life are constrained.

Technical Context

The LTC1864LIMS8#TRPBF implements a switched-capacitor SAR architecture with integrated sample-and-hold, operating exclusively on a single 2.7V–3.6V supply. Its conversion timing is fixed at 3.7–4.66 µs, synchronized by the rising edge of CONV and followed by serial readout via SDO on falling SCK edges.

It uses a true differential input pair (IN+, IN–) referenced to an externally supplied VREF (1V to VCC), with high-impedance analog inputs (±1 µA leakage) and 12 pF input capacitance in sample mode. The device powers down automatically between conversions, making it suitable for burst-mode sampling in energy-constrained systems.

Key Specifications

Pinout & Package

Package: 8-lead plastic MSOP (MS8), 3.0 mm × 3.0 mm × 0.86 mm, 0.65 mm pitch, lead coplanarity ≤ 0.102 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7980BRMZ and LTC2378-16IMS8#PBF, the LTC1864LIMS8#TRPBF uniquely balances 16-bit resolution, true differential input, sub-500 µA active current, and auto shutdown - making it the only viable choice for space- and energy-constrained systems requiring high linearity without external gain or reference conditioning.

Availability

LTC1864LIMS8#TRPBF is available at Aetrix Electronics and suitable for portable instrumentation, isolated data acquisition, and low-power sensor interface applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LTC1864LIMS8#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 acquired Linear Technology in 2017 and maintains its high-performance analog product lines, including precision data converters, references, and signal conditioning ICs.

The LTC1864LIMS8#TRPBF belongs to Linear's legacy µPower SAR ADC family, designed specifically for compact, battery-operated instrumentation where resolution, power efficiency, and ease of integration are prioritized over raw speed.

FAQ

What is the maximum sampling rate of the LTC1864LIMS8#TRPBF?

The LTC1864LIMS8#TRPBF supports a maximum sampling rate of 150 ksps. This is achieved with a fixed conversion time of 3.7–4.66 µs per sample, followed by serial readout. At lower rates, the device automatically powers down between conversions to reduce average current - e.g., drawing just 10 µA at 1 ksps. This behavior is inherent to the LTC1864LIMS8#TRPBF's architecture and requires no external control logic.

Does the LTC1864LIMS8#TRPBF support true differential input?

Yes, the LTC1864LIMS8#TRPBF features a true differential analog input pair (IN+, IN–) that measures the voltage difference between the two pins. This architecture provides common-mode noise rejection and enables accurate measurement of small differential signals - such as those from bridge sensors or thermocouples - without requiring external instrumentation amplifiers. The LTC1864LIMS8#TRPBF does not support single-ended input modes.

What reference voltage range is supported by the LTC1864LIMS8#TRPBF?

The LTC1864LIMS8#TRPBF accepts an external reference voltage (VREF) ranging from 1V to VCC (2.7V–3.6V). This flexibility allows direct interfacing with low-voltage precision references (e.g., LT1460) or rail-to-rail operation when VREF is tied to VCC. The reference input exhibits very low leakage (±1 µA), minimizing loading error - a key design advantage of the LTC1864LIMS8#TRPBF in high-impedance reference configurations.

Is the LTC1864LIMS8#TRPBF pin-compatible with any lower-resolution alternatives?

Yes, the LTC1864LIMS8#TRPBF is pin-compatible with the 12-bit LTC1860L and LTC1861L families in the same MSOP-8 package. This allows direct replacement to upgrade resolution without PCB layout changes. However, note that the LTC1864LIMS8#TRPBF requires updated firmware to handle 16-bit data words and different timing margins - especially regarding CONV hold time and SDO enable delay (t_en ≤ 120 ns).

What is the guaranteed integral nonlinearity (INL) specification for the LTC1864LIMS8#TRPBF?

The LTC1864LIMS8#TRPBF guarantees ±8 LSB maximum integral nonlinearity over temperature (0°C to 70°C for the 'C' grade; –40°C to 85°C for the 'I' grade). This specification applies across the full 16-bit code range and ensures monotonicity and predictable transfer function deviation - critical for applications like closed-loop control or precision calibration where code-to-code consistency matters. The typical INL is ±6 LSB, as confirmed in the LTC1864LIMS8#TRPBF datasheet.