Analog Devices Inc. LTC6240IS8#PBF

Overview

LTC6240IS8#PBF from Analog Devices (formerly Linear Technology) is a single-channel, rail-to-rail output, low-noise CMOS operational amplifier optimized for precision signal conditioning in space- and power-constrained industrial and medical systems. It delivers 18MHz gain bandwidth, 10V/μs slew rate, 550nV_P-P 0.1Hz–10Hz noise, 125μV max input offset voltage, and guaranteed ≤1pA input bias current over –40°C to +85°C - enabling high-fidelity amplification of photodiode, transducer, and sensor outputs.

For engineers reviewing the LTC6240IS8#PBF datasheet, LTC6240IS8#PBF pinout, LTC6240IS8#PBF application, or LTC6240IS8#PBF equivalent, key selection criteria include ultra-low input bias current for high-impedance sources, sub-1μV/°C offset drift stability across temperature, rail-to-rail output swing within 30mV of supply rails, and SO-8 package compatibility with guard-ring PCB layouts for leakage-sensitive designs.

Technical Context

The LTC6240IS8#PBF employs a proprietary CMOS input stage with guarded input pins and low-input-capacitance topology (3.5pF differential, 3pF common-mode), enabling stable operation with high-source-impedance sensors without external compensation. Its unity-gain-stable architecture supports direct use in transimpedance, instrumentation, and active filter configurations without phase-margin degradation.

Internally compensated for 18MHz GBW at 2.8V–6V single-supply or ±2.5V dual-supply operation, it maintains >100dB PSRR and >80dB CMRR over its full common-mode range (0V to V_S–1.5V), with output stage capable of sourcing/sinking ≥5mA while swinging to within 30mV of either rail - critical for maximizing dynamic range in low-voltage data acquisition systems.

Key Specifications

Pinout & Package

Package: 8-lead plastic SO (SO-8), RoHS-compliant, lead-free finish, 150°C max junction temperature, θ_JA = 190°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, low-input-bias op amp applications.

Compared with ADA4530-1ARZ and OPA377AIDR, the LTC6240IS8#PBF uniquely balances pA-level input bias, 18MHz bandwidth, rail-to-rail output, and –40°C to +85°C guaranteed operation in an industry-standard SO-8 package - making it optimal for ruggedized medical and industrial signal chains where both precision and reliability are non-negotiable.

Availability

LTC6240IS8#PBF is available at Aetrix Electronics and suitable for photodiode amplification, medical sensor front-ends, and high-impedance transducer interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC6240IS8#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 technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC6240 family was designed specifically for ultra-low-noise, ultra-low-input-bias precision amplification in demanding sensor and instrumentation applications - emphasizing stability, low drift, and robustness in real-world PCB environments.

FAQ

What is the maximum guaranteed input bias current for LTC6240IS8#PBF over its full operating temperature range?

The LTC6240IS8#PBF guarantees ≤1pA maximum input bias current across its specified –40°C to +85°C operating temperature range, verified per datasheet Electrical Characteristics table (LTC6240I grade). This specification applies to the SO-8 package variant and is critical for maintaining accuracy in high-impedance sensor interfaces where leakage currents dominate error budgets.

Does LTC6240IS8#PBF support true rail-to-rail output swing, and what is the worst-case voltage margin at full load?

Yes, the LTC6240IS8#PBF provides rail-to-rail output swing, with worst-case margins of ≤30mV from V+ and ≤30mV from V– under 5mA load conditions across –40°C to +85°C. This performance is confirmed in the "Output Voltage Swing" section of the datasheet and enables full utilization of 3.3V or 5V supply rails in precision data acquisition systems.

Can LTC6240IS8#PBF operate from a single 3.3V supply, and what is its minimum supply voltage?

Yes, the LTC6240IS8#PBF is fully specified for single-supply operation down to 2.8V, making it compatible with standard 3.3V logic and analog domains. Its minimum supply voltage is guaranteed by PSRR testing and remains functional at 2.8V with full AC/DC specifications maintained - ideal for battery-powered portable instrumentation.

What is the 0.1Hz–10Hz input noise voltage of LTC6240IS8#PBF, and how does it compare to legacy precision op amps?

The LTC6240IS8#PBF delivers 550nV_P-P 0.1Hz–10Hz input noise voltage - a >50% improvement over typical precision CMOS op amps of its era (e.g., ~1.2μV_P-P). This low 1/f noise enables stable DC-coupled amplification of slow biological and environmental signals without introducing baseline wander or requiring complex AC-coupling networks.

Is LTC6240IS8#PBF unity-gain stable, and does it require external compensation capacitors?

Yes, the LTC6240IS8#PBF is internally compensated for unity-gain stability and requires no external compensation components. It maintains >45° phase margin at gain = 1 with 5pF capacitive load, allowing direct use in buffer, follower, and transimpedance configurations without risk of oscillation - simplifying design and reducing board area.