Analog Devices Inc. LT1490CMS8#PBF

Overview

LT1490CMS8#PBF from Analog Devices (formerly Linear Technology) is a dual rail-to-rail input and output micropower operational amplifier in an 8-lead MSOP package. It operates from total supply voltages of 2V to 44V, draws ≤50µA per amplifier, delivers ±20mA output current, supports input common-mode range from –0.4V to 44V, and maintains rail-to-rail output swing - ideal for battery monitoring and sensor conditioning in low-power industrial systems.

For engineers reviewing the LT1490CMS8#PBF datasheet, LT1490CMS8#PBF pinout, LT1490CMS8#PBF application, or LT1490CMS8#PBF equivalent, key selection criteria include its reverse-battery protection to 18V, 200kHz gain-bandwidth product, 98dB CMRR, 1500V/mV open-loop gain, and ability to drive 10,000pF capacitive loads with optional compensation - all critical for precision single-supply signal conditioning.

Technical Context

The LT1490CMS8#PBF employs a dual-input-stage architecture (NPN and PNP) enabling operation with inputs up to 44V above V– and even 0.3V above V+, while maintaining high impedance and no phase reversal. Its unique input stage allows full rail-to-rail common-mode range on supplies as low as 2V, with built-in 1kΩ series resistors and diodes protecting inputs down to 22V below V–.

Internally compensated for stability with ≥200pF capacitive loads, it achieves unity-gain stability and supports optional 0.22µF + 150Ω output compensation to safely drive up to 10,000pF. The amplifier remains functional with V+ removed (shutdown mode), drawing <0.1nA input bias current even when inputs are at 44V relative to V–.

Key Specifications

Pinout & Package

LT1490CMS8#PBF is housed in an 8-lead MSOP (Mini Small Outline Package) with 0.5mm lead pitch, 3.0mm × 3.0mm body, and exposed pad for thermal enhancement. The package is RoHS-compliant and rated for –40°C to 85°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual micropower rail-to-rail op amp applications.

Compared with LT1490AEMS8#PBF and AD8602ARMZ, the LT1490CMS8#PBF uniquely balances ultra-low quiescent current (50µA), wide 2–44V supply range, and robust reverse-battery protection - making it irreplaceable for high-voltage micropower sensing where accuracy is secondary to reliability and longevity.

Availability

LT1490CMS8#PBF is available at Aetrix Electronics and suitable for battery monitoring, sensor signal conditioning, 4–20mA transmitters, and micropower active filters requiring stable component supply across industrial, medical, and energy infrastructure programs.

Supply support for LT1490CMS8#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 continues to manufacture, qualify, and support its precision analog portfolio under the ADI brand.

The LT1490 family was designed by Linear Technology specifically for micropower, rail-to-rail signal conditioning in harsh, wide-supply industrial and portable environments - emphasizing robustness, extended common-mode range, and reverse-polarity resilience over raw speed or ultra-low offset.

FAQ

What is the maximum capacitive load the LT1490CMS8#PBF can drive without external compensation?

The LT1490CMS8#PBF is internally compensated to drive at least 200pF of capacitive load under any output loading condition. For loads exceeding 200pF - up to 10,000pF - optional external compensation using a 0.22µF capacitor in series with a 150Ω resistor between output and ground is required to maintain stability and prevent overshoot.

Does the LT1490CMS8#PBF support true rail-to-rail input operation when powered from a 3V single supply?

Yes. The LT1490CMS8#PBF specifies a single-supply input range of –0.4V to 44V, meaning its inputs operate fully rail-to-rail - including down to 0.4V below ground - on a 3V supply (0V to 3V). This enables accurate sensing of signals near ground or VCC without clipping or phase reversal.

Can the LT1490CMS8#PBF be used in a reverse-battery configuration where V– is at +12V and V+ is at 0V?

No - reverse-battery protection applies only when the polarity of the supply is inverted (i.e., V+ connected to system ground and V– connected to negative potential). In the scenario described, the device would experience 12V reverse bias across its supply pins, exceeding the absolute maximum reverse supply rating of 18V but violating normal operating polarity. The LT1490CMS8#PBF must be connected with correct V+ and V– polarity to function.

What is the guaranteed operating temperature range for the LT1490CMS8#PBF?

LT1490CMS8#PBF is specified and production-tested over the commercial temperature range of 0°C to 70°C. While characterized and expected to perform across –40°C to 85°C, only the 'I' grade (e.g., LT1490IMS8#PBF) is guaranteed and tested over the full industrial range. Designers requiring –40°C to 85°C operation should select the 'I' variant.

How does the LT1490CMS8#PBF achieve input operation beyond the positive supply rail?

The LT1490CMS8#PBF uses a dual-input-stage architecture with Schottky diodes in the NPN input stage collector, allowing inputs to operate up to 0.3V above V+ without damage or phase reversal. At this overvoltage, input bias current rises to ~4µA and offset voltage shifts to ~700µV - documented behavior, not fault condition.