Texas Instruments LPC662AIM

Overview

LPC662AIM from Texas Instruments (formerly National Semiconductor) is a low-power CMOS dual operational amplifier optimized for single-supply operation across +5V to +15V. It delivers rail-to-rail output swing, ultra-low input bias current (2 fA), 3 mV input offset voltage, and 0.11 V/µs slew rate - enabling precision signal conditioning in battery-powered sensor interfaces and high-impedance analog front-ends.

For engineers reviewing the LPC662AIM datasheet, LPC662AIM pinout, LPC662AIM application, or LPC662AIM equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, application-specific implementation guidance, and two confirmed alternative parts with documented functional trade-offs.

Technical Context

The LPC662AIM uses an unconventional topology where the output is taken directly from the integrator stage - not a traditional unity-gain buffer - enabling true rail-to-rail swing while maintaining stability into 5 kΩ loads. Its compound integrator includes dual feed-forward paths (C_f and C_ff) and a push-pull output stage capable of sourcing/sinking ≥16 mA at V₊ = 5V.

This architecture yields asymmetric large-signal gain: ≥400 V/mV when sinking (enhanced by four gain stages), but ≥200 V/mV when sourcing (three-stage path). Input common-mode range extends to ground, and CMRR remains ≥70 dB over −40°C to +85°C - critical for DC-coupled instrumentation in industrial sensing.

Key Specifications

Pinout & Package

Package: 8-pin SOIC (Small Outline Integrated Circuit), NS Package Number M08A, RoHS-compliant tin (Sn) lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual low-power CMOS operational amplifier applications.

Compared with LMC662IMX/NOPB and TLC27L2CDR, the LPC662AIM uniquely combines femtoamp input bias, rail-to-rail output, and 3 mV offset in a single SOIC-8 package - making it the only option among the three for precision, single-supply, high-impedance analog signal chains requiring long-term stability.

Availability

LPC662AIM is available at Aetrix Electronics and suitable for high-impedance sensor interfaces, precision current-to-voltage conversion, and single-supply active filtering requiring stable component supply across industrial, medical, and IoT design cycles.

Supply support for LPC662AIM 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

Texas Instruments acquired National Semiconductor in 2011 and maintains full legacy support for its precision analog portfolio, including the LPC662 family.

The LPC662AIM belongs to National's low-power CMOS op-amp product line, designed specifically for single-supply, high-impedance, micropower applications in portable instrumentation and sensor signal conditioning.

FAQ

What is the maximum capacitive load the LPC662AIM can drive without oscillation?

The LPC662AIM can drive up to 100 pF without external compensation when configured as a unity-gain follower. For larger loads (e.g., 500 pF), add a 50–100 Ω series resistor at the output and a 5–10 pF capacitor from inverting input to output. This restores phase margin above 50° while preserving low-frequency response - verified in DS010548-4 and DS010548-5. The LPC662AIM's topology inherently limits instability risk compared to conventional op-amps due to its compound integrator design.

Does the LPC662AIM support true rail-to-rail input common-mode range?

No - the LPC662AIM features rail-to-rail *output* swing, but its input common-mode range extends only to V− (ground) and up to V+−1.9V (at V+ = 5V). This means it accepts inputs down to ground in single-supply use, but cannot handle signals near V+ without clipping. The datasheet specifies "Input Common-Mode Voltage Range" as −0.1V to V+−2.3V under standard conditions - a key distinction from true rail-to-rail input op-amps like the LMC6482. This limitation must be accounted for in high-side sensing applications.

Can the LPC662AIM operate from a 3.3V supply?

No - the LPC662AIM has a minimum specified supply voltage of +4.75V per Absolute Maximum Ratings and Operating Ratings tables. Attempting operation at 3.3V will result in undefined behavior, degraded rail-to-rail swing, and potential failure to meet AC/DC specifications. For 3.3V-compatible alternatives, consider the LMC6482 or TLV2462, which are explicitly characterized down to 2.7V. The LPC662AIM is optimized for 5V and higher single-supply systems.

How does the LPC662AIM's topology affect stability with resistive loads below 5 kΩ?

The LPC662AIM's unconventional integrator-based topology delivers higher open-loop gain into 5 kΩ loads (≥200 V/mV) but degrades to ≥100 V/mV at 500 Ω - as specified in the Large Signal Voltage Gain table. Stability is maintained down to 500 Ω per datasheet Note 7, but gain reduction must be compensated in closed-loop design. Unlike traditional op-amps, it does not require external compensation for purely resistive loads; however, output current capability drops to 13 mA sourcing/sinking at V+ = 5V, limiting drive strength in low-impedance applications.

Is the LPC662AIM pin-compatible with the LPC662IM variant?

Yes - LPC662AIM and LPC662IM share identical SOIC-8 packaging (NS M08A), pinout, electrical specifications, and temperature rating (−40°C to +85°C). The "A" suffix denotes tape-and-reel packaging (LPC662AIMX/NOPB) or tube (LPC662AIM/NOPB); "I" indicates tube-only ordering (LPC662IM/NOPB). Both are functionally interchangeable in PCB layout and schematic design - no footprint or netlist changes required when substituting between them.