Analog Devices Inc. LT1358CS8#PBF

Overview

LT1358CS8#PBF from Analog Devices (formerly Linear Technology) is a dual high-speed voltage-feedback operational amplifier with 25MHz gain bandwidth, 600V/µs slew rate, and 2.5mA maximum supply current per amplifier. It features matched high-impedance inputs, unity-gain stability, and C-Load™ drive capability for any capacitive load - making it ideal for precision data acquisition systems, active filters, and photodiode amplification.

For engineers reviewing the LT1358CS8#PBF datasheet, LT1358CS8#PBF pinout, LT1358CS8#PBF application, or LT1358CS8#PBF equivalent, key selection criteria include its 8-pin SOIC package, ±2.5V to ±15V supply range, 8nV/√Hz input noise, 115ns 0.1% settling time (10V step), and guaranteed operation from –40°C to 85°C.

Technical Context

The LT1358CS8#PBF employs a unique hybrid topology combining voltage-feedback input structure with current-feedback slewing behavior. Its complementary NPN/PNP emitter-follower inputs provide first-order bias-current cancellation, while internal 500Ω input resistors and mirrored current sources define gain node dynamics and slew rate proportionality to differential input voltage.

Stability across all capacitive loads is achieved via bootstrapped RC compensation that adapts to load conditions: under light loads the network is inactive; under heavy capacitive loading, added capacitance lowers unity-gain frequency and introduces phase-boosting zero to maintain ≥0° phase margin - eliminating need for external isolation resistors in coaxial cable driving applications.

Key Specifications

Pinout & Package

LT1358CS8#PBF is housed in an 8-pin plastic SOIC (S8) package, 3.9mm × 4.9mm body, 1.27mm pitch, RoHS-compliant lead-free finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual high-speed op amp applications.

Compared with LT1358CS8#PBF, LT1362CS8#PBF offers 2× bandwidth at +60% supply current, while LT1355CS8#PBF trades 50% bandwidth and 60% slew for 60% lower current - positioning LT1358CS8#PBF as the optimal balance for general-purpose high-speed analog signal chains requiring stability, noise performance, and moderate power.

Availability

LT1358CS8#PBF is available at Aetrix Electronics and suitable for data acquisition systems, photodiode amplifiers, DAC output buffering, and active filter designs requiring stable component supply across industrial, test equipment, and medical OEM programs.

Supply support for LT1358CS8#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 maintains full product support, manufacturing, and qualification for legacy Linear op amps including the LT1358 family.

The LT1358 series was designed as a dual high-speed precision op amp targeting applications demanding both wide bandwidth and low distortion - especially where unity-gain stability and capacitive load drive were historically trade-offs.

FAQ

What is the maximum capacitive load the LT1358CS8#PBF can drive while remaining stable?

The LT1358CS8#PBF is specified as stable with "any capacitive load" - a feature branded C-Load™ by Linear Technology. This means no external isolation resistor is required regardless of load capacitance (e.g., 1000pF coaxial cable, 10nF LCD panel traces, or 100nF bulk decoupling). Stability is maintained via adaptive internal compensation that adds phase-boosting zero under heavy capacitive loading, ensuring ≥0° phase margin even at extremes. Measured overshoot remains ≤27% up to 1000pF in unity-gain configuration.

Does the LT1358CS8#PBF support single-supply operation?

Yes, the LT1358CS8#PBF supports single-supply operation with rail-to-rail input common-mode range extending to within 1.1V of V– and 13.4V below V+ at ±15V supplies - meaning it functions with V– = 0V and V+ = 5V, 12V, or 15V. Input voltage range is specified from –0.9V to +13.4V (V– = 0V, V+ = 15V), and output swing reaches ±3V into 150Ω on ±5V supplies. For true single-supply 0–5V systems, level-shifting or AC-coupling may be needed to keep inputs within valid CM range.

What is the typical input bias current polarity of the LT1358CS8#PBF, and why does it vary?

The LT1358CS8#PBF uses complementary NPN/PNP input transistors whose base currents oppose each other - resulting in net input bias current (IB) that can be either positive or negative depending on beta mismatch between devices. Datasheet specifies IB = 120–500nA (±2.5V to ±15V), with no guaranteed polarity. This variation arises from process tolerances in transistor matching; however, input offset current (IOS = 40–120nA) remains tightly controlled because it depends only on mismatch magnitude, not polarity. For DC-critical applications, balanced source impedances on both inputs minimize offset voltage contribution.

How does the slew rate of the LT1358CS8#PBF change with gain configuration?

The LT1358CS8#PBF's slew rate is proportional to differential input voltage, not closed-loop gain - a consequence of its current-feedback-like slewing architecture. In a gain-of-10 inverting amplifier, a 10V output step produces only a 1V input step, yielding lower effective slew than in unity-gain (10V input step for same output). Datasheet tests SR at AV = –2 (300–600V/µs); thus, SR exceeds 600V/µs in AV = 1 or AV = –1, and decreases in higher gains. This behavior is confirmed by the "Slew Rate vs Input Level" curve (G24), showing SR peaks near 10Vpp input and declines at lower amplitudes.

Is the LT1358CS8#PBF pin-compatible with other dual op amps in SO-8 packages?

No, the LT1358CS8#PBF uses a nonstandard SO-8 pinout optimized for dual-amplifier symmetry: Pins 1/2/3/4 serve Amplifier A (–IN, +IN, V+, OUT), while Pins 5/6/7/8 serve Amplifier B (OUT, V–, –IN, +IN). This differs from industry-standard dual op amp pinouts (e.g., LM358, TL072, OP27) which place V+ and V– on opposite ends. Interchanging LT1358CS8#PBF with standard dual op amps will cause incorrect power connections and functional failure. Always verify pin mapping before PCB layout or replacement.