Analog Devices Inc. LTC6240CS8#PBF

Overview

LTC6240CS8#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 low-voltage, high-impedance sensor interfaces. 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 - enabling accurate amplification of weak signals from photodiodes, piezoelectric transducers, and medical biosensors.

For engineers reviewing the LTC6240CS8#PBF datasheet, LTC6240CS8#PBF pinout, LTC6240CS8#PBF application, or LTC6240CS8#PBF equivalent, key selection criteria include its 1pA max input bias current at 25°C, rail-to-rail output swing within 30mV of supply rails, 2.8V to 6V single-supply operation, and SO-8 package compatibility with PCB guard ring layouts for leakage-sensitive designs.

Technical Context

The LTC6240CS8#PBF employs a proprietary CMOS input stage with ultra-low gate leakage, enabling sub-picoampere bias current performance critical for high-impedance source interfacing. Its unity-gain-stable architecture supports direct use in transimpedance configurations without external compensation.

It features a fully differential input common-mode range extending to the negative rail and rail-to-rail output stage capable of driving loads down to 1kΩ while maintaining linearity and low distortion across its 18MHz bandwidth - making it suitable for both DC-coupled precision buffering and AC-coupled wideband signal processing.

Key Specifications

Pinout & Package

The LTC6240CS8#PBF is housed in an 8-pin plastic SO (Small Outline) package with exposed pad not connected internally; thermal performance characterized at θ_JA = 190°C/W. The package supports standard reflow and is compatible with PCB guard ring layouts to suppress surface leakage.

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 OPA377AIDBVR, the LTC6240CS8#PBF uniquely balances 1pA max input bias, 18MHz bandwidth, and rail-to-rail output in an SO-8 package - making it the optimal choice for high-fidelity, medium-speed sensor signal chains requiring both precision and speed.

Availability

LTC6240CS8#PBF is available at Aetrix Electronics and suitable for photodiode amplification, medical biosensor interfaces, and low-voltage data acquisition front-ends requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LTC6240CS8#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 LTC6240CS8#PBF belongs to ADI's legacy Linear Technology precision op amp portfolio, engineered specifically for low-noise, low-input-bias applications in medical instrumentation, analytical equipment, and high-impedance sensor signal conditioning.

FAQ

What is the maximum guaranteed input bias current for LTC6240CS8#PBF over temperature?

The LTC6240CS8#PBF guarantees ≤1pA maximum input bias current at 25°C. Over the full 0°C to 70°C specified temperature range, input bias current remains ≤75pA per Electrical Characteristics table (LTC6240C grade). This ensures predictable leakage performance in photodiode and pH probe circuits across commercial operating conditions.

Does LTC6240CS8#PBF support true rail-to-rail input common-mode range?

No - the LTC6240CS8#PBF features rail-to-rail *output* swing but only extends its input common-mode range to the negative rail (V–), not to V+. At 5V supply, the input common-mode range is specified as 0V to 3.5V (i.e., up to 1.5V below V+), which is sufficient for most single-supply sensor interfaces where the signal stays near mid-rail or ground-referenced.

Can LTC6240CS8#PBF drive a 1000pF capacitive load directly?

No - the LTC6240CS8#PBF is unity-gain stable into resistive loads but exhibits phase margin degradation with capacitive loads >50pF. Driving 1000pF requires isolation via a series resistor (≥200Ω) or use of a dedicated capacitive-load-drive variant like LTC6240HV. Always verify stability with SPICE simulation or bench testing when driving cables or ADC input capacitance.

What is the minimum supply voltage for LTC6240CS8#PBF to meet all specifications?

The LTC6240CS8#PBF maintains full specification compliance down to 2.8V total supply voltage (V+ to V–), as confirmed in Absolute Maximum Ratings and Electrical Characteristics tables. Operation below 2.8V may result in reduced open-loop gain, increased offset voltage, or failure to achieve rail-to-rail output swing - verify functionality at 2.7V if required for ultra-low-power brownout scenarios.

Is LTC6240CS8#PBF pin-compatible with other op amps in the LTC624x family?

Yes - the LTC6240CS8#PBF shares identical SO-8 pinout with LTC6241CS8#PBF (dual) and LTC6242CGN#PBF (quad) for non-inverting/inverting input, output, and supply pins (pins 2, 3, 5, 4, 8). However, NC pins differ: LTC6240CS8#PBF has NC on pins 1/6/7, while LTC6241CS8#PBF uses all 8 pins functionally. Board reuse requires verification of NC pin handling and channel count requirements.