Analog Devices Inc. LT1125CSW#PBF

LT1125CSW#PBF Quad Operational Amplifier Summary

The LT1125CSW#PBF, manufactured by Analog Devices Inc., is a general-purpose, high-performance quad operational amplifier specifically engineered for demanding analog signal processing tasks. Offered in a 16-lead SO wide-body package, this device integrates four op amps into a single IC, optimizing board space for multi-channel precision applications. Distinguished by its exceptionally low input noise, fast slew rate, high gain-bandwidth product, and robust input/output performance, the LT1125CSW#PBF addresses the requirements of designers seeking low power consumption and high accuracy in compact, surface-mount layouts.

Highlights and Performance Specifications of LT1125CSW#PBF

• Low Input Noise: The amplifier achieves a typical noise density of 2.7 nV/√Hz at 1 kHz, with input noise voltage of 70 nVp-p across 0.1 Hz to 10 Hz, outperforming legacy OP-27 and OP-270/470 op amps in both noise and offset characteristics.

• Slew Rate: The typical slew rate is 4.5 V/μs, supporting rapid signal transients essential for high-speed, high-fidelity analog systems.

• Gain-Bandwidth Product: With a typical gain-bandwidth product of 12.5 MHz, the LT1125CSW#PBF enables high accuracy amplification in both DC and AC configurations.

• Input Offset: Maximum input offset voltages are tightly controlled (typically as low as 25–140 μV, depending on grade), supporting microvolt-level precision and minimizing drift over temperature.

• Low Input Bias/Offset Currents: Bias currents typically remain below 20 nA and offset currents below 30 nA, making the amplifier suitable for interfacing with high-impedance sources or precision sensing elements.

• High CMRR and PSRR: Minimum 112 dB common-mode rejection and 116 dB power-supply rejection ratios ensure signal fidelity in noisy industrial or instrumentation environments.

Recommended Uses for LT1125CSW#PBF

The LT1125CSW#PBF demonstrates versatility across a wide range of precision analog functions:

Instrumentation Amplifiers: The device supports high performance twoand three-op-amp configurations, enabling high accuracy and noise immunity in differential measurement systems.

Low Noise Signal Processing: Thanks to its low voltage and current noise, the LT1125CSW#PBF is ideal for sensor front ends, photodiode preamplifiers, and other systems requiring strong signal integrity.

Active Filters and Audio Applications: Its wide bandwidth and low distortion characteristics make the IC suitable for audio gain stages, active filters, and tape head preamplifiers.

Microvolt-Level Detection: The low offset and drift enable use in microvolt-accuracy threshold detection, strain gauge amplifiers, and infrared detector front ends that demand long-term stability.

Direct-Coupled Precision Stages: The high gain and DC accuracy support applications such as direct-coupled precision signal chains without the need for frequent recalibration.

Electrical Specifications and Thermal Data of LT1125CSW#PBF

Taking the typical operating point at room temperature and ±15V supply, the performance parameters are:

Input Offset Voltage: 30–140 μV (max, depending on grade and temperature range)

Input Bias Current: Typically 17–20 nA max

Input Voltage Range: ±12.2 V min, supporting wide input swing

Common-Mode Rejection Ratio (CMRR): 101–124 dB (min)

Power Supply Rejection Ratio (PSRR): 106–124 dB (min)

Output Swing: ±12 V min with 2 kΩ load

Supply Current: 2.3–2.75 mA per amplifier channel

Maximum Operating Temperature Range: 0°C to 70°C (for "C" grade)

Absolute Maximum Ratings: Supply voltage ±22V, storage −65°C to +150°C, output short-circuit duration indefinite

The device's low drift, strong channel separation, and robust short-circuit tolerance contribute to its reliability in both laboratory and field environments.

Packaging and Installation Information for LT1125CSW#PBF

The LT1125CSW#PBF is shipped in a 16-lead SO (Small Outline) Wide package—SOW—with a standard width of 7.50 mm (0.295"). This package type supports surface mounting, facilitating automated PCB assembly processes. The thermal resistance of the SOW package ensures reliable device operation within the recommended temperature limits. The pinout is designed for straightforward board layout and is suitable for multi-channel, high-density analog subsystems.

The device boasts RoHS3 compliance and has a Moisture Sensitivity Level (MSL) of 1 (unlimited shelf life under specified conditions), allowing it to be utilized in modern lead-free, environmentally conscious manufacturing environments.

Alternative or Substitute Devices for LT1125CSW#PBF

When evaluating the LT1125CSW#PBF for new or legacy designs, engineers may wish to compare or consider potential equivalents based on performance parameters and package compatibility. Some alternatives include:

Analog Devices LT1125 series in alternate packages (e.g., DIP or ceramic variants) and different temperature grades for extended or military use

Linear Technology LT1124 dual op amp (half the resources, same precision/performance core)

OP-470 or OP-270 series quad/dual op amps (industry standards, though with typically higher noise and/or offset)

Other quad precision low-noise op amps meeting similar noise density, offset, and bandwidth requirements from leading analog IC manufacturers

In retrofit or cost-down scenarios, careful attention should be paid to parameters such as input noise, offset voltage, supply current, package footprint, and long-term availability. Notably, the LT1125CSW#PBF surpasses many older models in terms of noise and drift performance.

Conclusion

The LT1125CSW#PBF quad low noise, high-speed precision op amp from Analog Devices combines exceptional signal accuracy, low noise, and versatile packaging, making it a top choice for engineers and procurement teams specifying parts for precision analog signal chain applications. Its advantage over competitive and prior-generation models lies in tight guaranteed specifications, robust operational range, and proven reliability, all while supporting modern lead-free manufacturing standards. Suitable for both new designs and performance upgrades of legacy systems, the LT1125CSW#PBF stands out as a premier solution for demanding analog environments.