Analog Devices Inc. LT1490ACS8#TRPBF

LT1490ACS8#TRPBF Dual Op-Amp Product Summary

The LT1490ACS8#TRPBF by Analog Devices is a general-purpose, dual-channel operational amplifier engineered for applications requiring both rail-to-rail input and output swing and extremely low power consumption. Housed in an 8-lead SOIC package, the device supports surface-mount assembly, making it ideal for compact PCB designs in modern portable and energy-sensitive systems.

Designed as part of the LT1490A/LT1491A family, the LT1490ACS8#TRPBF offers “Over-The-Top” input capability, which allows the input common-mode voltage to range up to 44V above the negative rail (V−), independent of the positive supply (V+). The device maintains stable operation over supply voltages ranging from 2V to 44V, providing substantial flexibility across a wide array of analog signal chain environments, including low-voltage battery-operated circuits and higher-voltage industrial subsystems.

-

Main Attributes and Use Cases of LT1490ACS8#TRPBF

The LT1490ACS8#TRPBF highlights several technical advantages essential for circuit designers. First, with an input offset voltage specification of 500μV (maximum), the amplifier ensures high accuracy in signal conditioning and measurement applications. Its rail-to-rail input and output stages allow designers to utilize the full dynamic range of the power supply—a critical benefit in both single-supply and split-supply systems.

The device’s typical micropower performance is distinguished by supply currents of just 40μA per amplifier (maximum 50μA) and broad operating temperature support up to 85°C. Key features include:

Over-The-Top input range, tolerating input voltages well beyond the supply rails (up to 44V).

Reverse battery protection to 18V, safeguarding against accidental supply swaps during device operation or system startup.

High output drive capability, sourcing or sinking up to 20mA per channel.

Capacitive load drive up to 10,000pF when externally compensated, facilitating direct interface with filters and remote sensors.

Target application areas for the LT1490ACS8#TRPBF span battery- or solar-powered measurement nodes, portable instrumentation, battery monitoring, supply current sensing, micropower active filters, and 4–20mA industrial transmitters. These are environments where low supply current, high voltage tolerance, and robust fault protection are paramount.

-

LT1490ACS8#TRPBF Essential Electrical Specs and Performance Indicators

Product selection is strongly guided by detailed performance data across operating conditions. Highlighted parameters for the LT1490ACS8#TRPBF include:

Input Offset Voltage: Maximum 500μV at 25°C, guaranteeing precision in low-level signal designs.

Input Bias Current: Typical 1nA, supporting high-impedance sensor interfaces.

Input Common Mode Range: 0V to 44V at 3V or 5V supply, exceeding conventional rail-to-rail limitations.

Output Swing: Within 10mV (typical, no load) of both rails at 3V and 5V supplies.

Gain Bandwidth Product: Typical 200kHz, with 90–180kHz over full industrial temperature.

Slew Rate: 0.06V/μs typical, balancing micropower operation with adequate dynamic response.

Power Supply Rejection Ratio (PSRR): Up to 98dB, supporting resilient performance in noisy supply environments.

Output Short-Circuit Current: up to ±25mA (short to GND, at ±15V supply), enabling robust output fault tolerance.

Absolute maximum supply voltage spans 44V, and the amplifier maintains specified operation over −40°C to 85°C ambient temperature, with extended grades available for −40°C to 125°C.

-

LT1490ACS8#TRPBF Internal Structure and Design Analysis

The LT1490ACS8#TRPBF employs a proprietary rail-to-rail input topology that preserves high impedance and linearity for common-mode input voltages significantly above the positive rail—a core competitive advantage for “Over-The-Top” applications. Integrated resistor networks protect the input from excursions 15V below V− and 44V above V−, simplifying protection component design around the op amp and reducing PCB area.

A carefully engineered output stage allows the part to drive substantial capacitive loads, facilitated by optional external compensation, and maintain stable operation at unity gain. Reverse battery protection is inherent, ensuring that current flow is minuscule under supply mishap conditions for up to 18V reverse voltage.

The part is unity-gain stable and carefully engineered to avoid output phase reversal, guaranteeing predictable system behavior even during saturation or overdrive fault events.

-

LT1490ACS8#TRPBF Packaging Details, Installation Methods, and Environmental Standards

The LT1490ACS8#TRPBF is housed in a standard 8-lead SOIC (Small Outline Integrated Circuit) package, with a 3.90mm body width, well-suited for automated assembly and high-density PCB layouts. The device also supports alternative footprints such as MSOP, PDIP, and DFN for development flexibility (see family documentation).

Environmental compliance is assured: the device meets RoHS3 standards, is REACH unaffected, and offers MSL 1 (unlimited floor life at ≤30°C/85% RH). For system-level export and regulatory needs, it is classified with an ECCN of EAR99.

-

Alternative and Substitute Models for LT1490ACS8#TRPBF

When evaluating the LT1490ACS8#TRPBF for new or legacy designs, engineers may consider potential equivalents within the Analog Devices LT1490A/LT1491A family. The principal differences among these family members are the amplifier count (dual or quad), package styles, and operating temperature grades:

LT1490A Series: Dual operational amplifiers in MSOP, SOIC, PDIP, and DFN options; extended temperature grades available (–40°C to 125°C).

LT1491A Series: Quad operational amplifiers suitable for higher density integration; available in SOIC, PDIP, S, and 16-lead DFN.

For applications demanding higher bandwidth or slew rate, alternative families such as the LT1636 (Micropower R-R Input/Output Op Amp) or the MCP6002 from Microchip (dual, general-purpose CMOS op amp) may merit comparison. It is crucial to validate parameters such as input offset performance, supply range, power consumption, and rail-to-rail capability when considering substitutes for analog signal chain integrity.

-

Conclusion

The Analog Devices LT1490ACS8#TRPBF dual op amp stands out for its combination of ultra-low supply current, extended input voltage tolerance, robust output drive, and comprehensive protection mechanisms in a compact SOIC package. Its “Over-The-Top” input range and fault-tolerant features answer the stringent requirements of modern low-power analog systems—particularly those that must sustain operation across wide supply voltages and demanding field conditions. For engineers and buyers developing portable measurement, sensor, or industrial IoT front ends, the LT1490ACS8#TRPBF is a prime candidate for consideration, backed by a well-documented performance pedigree and versatile package and temperature options. When selecting or replacing operational amplifiers, the LT1490ACS8#TRPBF and its immediate family should be evaluated in context of application-specific precision, power, and protection demands.