Analog Devices Inc. LTC1199LIMS8#PBF

Overview

LTC1199LIMS8#PBF from Analog Devices (formerly Linear Technology) is a 10-bit, 250ksps successive-approximation ADC with integrated 2-channel analog multiplexer, single 2.7V supply operation, auto shutdown, and SPI/MICROWIRE-compatible 4-wire serial interface in 8-pin MSOP package. It delivers 58dB SNR at 50kHz input and consumes only 0.8mA typical supply current during full-speed sampling - ideal for battery-powered data acquisition in portable instrumentation.

For engineers reviewing the LTC1199LIMS8#PBF datasheet, LTC1199LIMS8#PBF pinout, LTC1199LIMS8#PBF application, or LTC1199LIMS8#PBF equivalent, key selection considerations include its software-selectable MUX configuration (single-ended CH0/CH1 or differential CH0–CH1), VCC-referenced internal reference, 2.7V–4V supply range, 2.2mW power dissipation at 250ksps, and guaranteed no missing codes over temperature.

Technical Context

The LTC1199LIMS8#PBF implements a switched-capacitor SAR architecture with on-chip sample-and-hold and a configurable 2-channel analog multiplexer. Its digital interface uses a synchronous half-duplex 4-wire protocol (CS, CLK, DIN, DOUT), where a 4-bit configuration word selects channel mode (SGL/DIFF), polarity (ODD/SIGN), and dummy bit insertion to extend acquisition time.

Unlike the LTC1197L series, it lacks an external VREF pin - reference is internally tied to VCC - and supports only unipolar transfer characteristics. Conversion timing is clock-driven: tCONV = 2.9µs (10.5 CLK cycles at fCLK = 3.5MHz), with CS-controlled power-down enabling linear supply current scaling down to µA-level standby.

Key Specifications

Pinout & Package

Package: 8-lead MSOP (3mm × 3mm, 0.65mm pitch), RoHS-compliant, moisture-sensitive level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit SAR ADC applications.

Compared with ADS7822U and MAX11100ETE+, the LTC1199LIMS8#PBF uniquely combines 10-bit resolution, integrated 2-channel MUX, and VCC-referenced operation in a 3mm × 3mm MSOP - delivering optimal channel density and BOM simplicity for compact, battery-operated systems.

Availability

LTC1199LIMS8#PBF is available at Aetrix Electronics and suitable for portable instrumentation, industrial sensor nodes, handheld test equipment, and energy harvesting data loggers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LTC1199LIMS8#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 LTC1199LIMS8#PBF belongs to ADI's legacy Linear Technology precision data acquisition product line, engineered for ultra-low-power, high-speed SAR ADC applications in space- and energy-constrained embedded systems.

FAQ

What is the maximum sampling rate of the LTC1199LIMS8#PBF at 2.7V supply?

The LTC1199LIMS8#PBF achieves a maximum sampling rate of 250ksps when operated at VCC = 2.7V with fCLK = 3.5MHz. This is specified over the full –45°C to 85°C industrial temperature range and corresponds to a conversion time of 2.9µs. Performance degrades linearly below this clock rate, and the device maintains no missing codes guarantee across the entire operating range.

Does the LTC1199LIMS8#PBF require an external reference voltage?

No, the LTC1199LIMS8#PBF does not require an external reference voltage. It uses an internal reference tied directly to the VCC pin, eliminating the need for external reference components. This simplifies design and reduces cost, though full-scale range scales with VCC - e.g., 2.7V supply yields 0–2.7V input range. The LTC1197L series, in contrast, provides a dedicated VREF pin for independent reference control.

How is channel selection configured on the LTC1199LIMS8#PBF?

Channel selection on the LTC1199LIMS8#PBF is configured via a 4-bit word shifted into the DIN pin after CS goes low: start bit ('1'), followed by SGL/DIFF (bit 1), ODD/SIGN (bit 2), and dummy bit (bit 3). This selects among four modes: CH0–GND (single-ended), CH1–GND (single-ended), CH0–CH1 (differential), or CH1–CH0 (inverted differential). The configuration occurs before each conversion and is not latched.

Can DIN and DOUT be connected to the same MCU pin on the LTC1199LIMS8#PBF?

Yes, DIN and DOUT can be wired together to a single bidirectional MCU GPIO pin. The LTC1199LIMS8#PBF drives DOUT low on the 4th falling CLK edge after the start bit, so the MCU must release the line (configure as input) before that edge to avoid contention. This 3-wire mode reduces interconnect count and is demonstrated in application circuits interfacing with 8051-family microcontrollers.

What is the supply current of the LTC1199LIMS8#PBF during active conversion and shutdown?

During full-speed sampling at 250ksps and VCC = 2.7V, the LTC1199LIMS8#PBF draws 0.8mA typical supply current (2.2mW). In shutdown mode (CS high), supply current drops to 0.8µA typical - a 1000× reduction. Current scales linearly with sampling frequency, enabling precise power budgeting in duty-cycled applications like periodic sensor logging.