Analog Devices Inc. LTC1197LIMS8#TRPBF

Overview

LTC1197LIMS8#TRPBF from Analog Devices (formerly Linear Technology) is a 10-bit, 250ksps successive approximation ADC with differential analog input, internal sample-and-hold, and auto shutdown. It operates from a single 2.7V supply, draws only 0.8mA typical at full speed, and features SPI/MICROWIRE-compatible 3-wire serial I/O. It is used in portable instrumentation for high-resolution sampling of low-noise, rail-to-rail analog signals up to 2.7V.

For engineers reviewing the LTC1197LIMS8#TRPBF datasheet, LTC1197LIMS8#TRPBF pinout, LTC1197LIMS8#TRPBF application, or LTC1197LIMS8#TRPBF equivalent, key selection criteria include its 2.7V operation, 10-bit no-missing-codes resolution, differential input architecture, 250ksps maximum sampling rate, and MSOP-8 package compatibility with space-constrained battery-powered systems.

Technical Context

The LTC1197LIMS8#TRPBF implements a switched-capacitor SAR architecture with integrated sample-and-hold and programmable reference input (VREF). Its differential input supports ratiometric measurement and direct connection to low-output-impedance sensors without gain stages.

It uses a synchronous 3-wire serial interface (CS, CLK, DOUT) with MSB-first output, requiring 14 clock cycles per conversion. Auto shutdown reduces supply current linearly with decreasing sampling frequency - down to sub-µA standby when CS is high.

Key Specifications

Pinout & Package

Package: 8-pin MSOP (3mm × 3mm, 0.65mm pitch), RoHS-compliant, moisture sensitivity 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 LTC1197LIMS8#TRPBF uniquely balances 10-bit precision, 250ksps speed, true differential input, and MSOP-8 size at 2.7V - making it optimal for space- and power-constrained portable instrumentation where 8-bit is insufficient and 12-bit adds unnecessary cost/complexity.

Availability

LTC1197LIMS8#TRPBF is available at Aetrix Electronics and suitable for portable instrumentation, battery-operated sensor interfaces, and compact industrial data loggers requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LTC1197LIMS8#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, 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 LTC1197LIMS8#TRPBF belongs to ADI's legacy Linear Technology precision data acquisition product line, designed specifically for micropower, high-resolution sampling in portable and energy-sensitive embedded systems.

FAQ

What is the maximum clock frequency supported by the LTC1197LIMS8#TRPBF?

The LTC1197LIMS8#TRPBF supports a maximum clock frequency of 3.5MHz when operating from a 2.7V supply. This corresponds to its rated 250ksps sampling rate. Exceeding this frequency may cause timing violations, increased INL error, or conversion failure - especially at temperature extremes or low VCC. Always verify timing margins using the tCYC (14-clock cycle) and tSMPL (1.5-clock sampling time) specifications from the datasheet.

Does the LTC1197LIMS8#TRPBF require an external reference voltage?

Yes, the LTC1197LIMS8#TRPBF requires an external reference voltage applied to the VREF pin. It accepts 0.2V to VCC + 0.05V, enabling flexible scaling (e.g., 2.5V for 250µV LSB or ratiometric use with a matched sensor excitation source). Unlike some ADCs, it does not include an internal reference; omitting VREF will result in undefined conversion results.

Can the LTC1197LIMS8#TRPBF interface directly with a microcontroller GPIO without level shifters?

Yes - the LTC1197LIMS8#TRPBF is fully compatible with 2.7V–3.3V microcontrollers. Its VIH is 1.9V (min) and VIL is 0.45V (max) at VCC = 2.7V, matching standard LVTTL and CMOS logic thresholds. No level shifting is needed when interfacing with modern ARM Cortex-M or RISC-V MCUs operating at 3.3V or lower.

What is the purpose of the auto shutdown feature in the LTC1197LIMS8#TRPBF?

The auto shutdown feature in the LTC1197LIMS8#TRPBF reduces supply current linearly as sampling frequency decreases - from 0.8mA at 250ksps down to ~0.25µA when idle (CS high). This eliminates external power-control circuitry and enables true micropower operation in duty-cycled systems like wireless sensor nodes, where the ADC samples briefly then sleeps for extended periods.

Is the LTC1197LIMS8#TRPBF pin-compatible with the standard LTC1197CMS8?

No - the LTC1197LIMS8#TRPBF is not pin-compatible with the 5V-oriented LTC1197CMS8. While both share the same MSOP-8 package and pin numbering, the LTC1197LIMS8#TRPBF is specified for 2.7V–4V operation and has different absolute maximum ratings, input thresholds, and clock timing. Interchanging them risks underperformance or damage due to mismatched voltage domains and timing margins.