Analog Devices Inc. LT1056CN8#PBF

Overview

LT1056CN8#PBF from Analog Devices (formerly Linear Technology) is a precision, high-speed JFET-input operational amplifier in an 8-lead PDIP package. It delivers 12 V/µs minimum slew rate, 6.5 MHz gain bandwidth product, 150 µV maximum input offset voltage, and 40 pA typical input bias current at 70°C - enabling high-fidelity signal conditioning in fast, low-error analog systems such as voltage-to-frequency converters and photodiode amplifiers.

For engineers reviewing the LT1056CN8#PBF datasheet, LT1056CN8#PBF pinout, LT1056CN8#PBF application, or LT1056CN8#PBF equivalent, this page provides verified DC precision, AC performance, thermal behavior, package-specific limitations, and real-world substitution guidance - all grounded in the official LT1055/LT1056 datasheet (Rev. 10556fd) and Linear Technology's validated specifications for the CN8 variant.

Technical Context

The LT1056CN8#PBF uses a JFET-input front-end with phase-reversal protection circuitry, eliminating output lock-up when the negative common-mode input limit is exceeded - a known failure mode in legacy LF155/LF156-class op amps. Its internal architecture balances speed and precision via higher quiescent current than the LT1055, enabling faster settling (e.g., 1.5–2 µs to 2 mV for DAC output amplification) without sacrificing input impedance (>10¹² Ω) or noise floor.

It operates over 0°C to 70°C ambient, supports ±15 V supplies (±20 V absolute max), and features dual balance pins (pins 1 & 8) for offset nulling using a 100 kΩ potentiometer tied to V+. Unlike bipolar-input op amps, its 1/f noise corner is low (≈28 Hz), and its 0.1–10 Hz peak-to-peak input noise is 2.5 µV (typ), making it suitable for precision DC-coupled, low-frequency measurement paths where microvolt-level stability matters.

Key Specifications

Pinout & Package

LT1056CN8#PBF is housed in an 8-lead narrow-body PDIP (N8) package (0.300" width), with JEDEC-standard pinout and 130°C/W junction-to-ambient thermal resistance. The plastic molding compound exerts mechanical stress on the die, resulting in wider offset voltage distribution vs. metal-can H-package variants - confirmed by datasheet G03 and G04 plots.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision JFET-input op amp applications.

Compared with LT1055CN8#PBF, the LT1056CN8#PBF trades 2.2 mA extra supply current for +2 V/µs slew rate and +1.5 MHz GBW - directly enabling 10× faster DAC settling and wider small-signal bandwidth. Versus TLC27L7CP, it offers 340× higher slew rate and dual-supply robustness but requires ±15 V infrastructure and dissipates more heat.

Availability

LT1056CN8#PBF is available at Aetrix Electronics and suitable for precision instrumentation, industrial DAC buffering, photodiode signal chains, and voltage-to-frequency conversion requiring stable component supply across long production lifecycles.

Supply support for LT1056CN8#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; Linear originally designed the LT1055/LT1056 family to bridge the gap between bipolar op amp precision and JFET op amp speed - targeting high-end test equipment and aerospace-grade analog signal paths.

The LT1056 belongs to Linear's precision JFET-input op amp product line, engineered specifically for applications demanding simultaneous microvolt offset, picoampere bias current, and megahertz-class bandwidth - such as logarithmic amplifiers, fast sample-and-hold circuits, and high-fidelity sensor front-ends.

FAQ

What is the guaranteed input offset voltage specification for LT1056CN8#PBF over temperature?

The LT1056CN8#PBF guarantees ≤150 µV input offset voltage at 25°C, and ≤500 µV maximum across the full 0°C to 70°C operating range per datasheet Table "ELECTRICAL CHARACTERISTICS" (page 4). This is the tightest offset spec available among JFET-input op amps in PDIP packaging at time of release.

Does LT1056CN8#PBF support phase reversal protection, and how is it implemented?

Yes, LT1056CN8#PBF includes built-in phase reversal protection, unlike LF155/LF156. As shown in the simplified schematic (page 15), Q1 blocks reverse conduction when the –IN pin drops below –12 V (with ±15 V supplies), preventing output latch-up in servo or closed-loop systems - a key reliability feature confirmed in AI05–AI08 test waveforms.

Can LT1056CN8#PBF replace LF156A in existing sockets without modification?

Yes, LT1056CN8#PBF is a direct socket-compatible replacement for LF156A, OP-16, and LF155A in 8-pin DIP footprints. Pinout matches exactly, and offset nulling (pins 1 & 8) uses the same 100 kΩ pot-to-V+ configuration - verified in Applications Information section (page 9) and AI1 diagram.

What is the typical 0.1 Hz to 10 Hz input noise voltage of LT1056CN8#PBF, and how does it vary with supply voltage?

The LT1056CN8#PBF exhibits 2.5 µV_P-P typical input noise in the 0.1 Hz–10 Hz band at ±15 V supplies (page 7, G08). Reducing supply to ±5 V lowers chip temperature, cutting this noise to ~1.5 µV_P-P - a design trade-off documented in the Noise Performance section (page 10) for ultra-low-drift applications.

How does the plastic N8 package affect long-term offset stability compared to the metal-can H package?

The N8 plastic package exerts mechanical stress on the JFET die, widening the offset voltage distribution and increasing drift versus the TO-5 H package - explicitly noted in Applications Information (page 10): "In the plastic N8 package the molding compound is in direct contact with the chip… JFET device matching and drift are degraded." H-package variants (e.g., LT1056ACH#PBF) are preferred for metrology-grade stability.