Texas Instruments LMC662CM

Overview

LMC662CM from Texas Instruments is a dual CMOS rail-to-rail output operational amplifier designed for precision single-supply operation, featuring 126dB open-loop voltage gain, ultra-low 2fA input bias current, and 1.1V/μs slew rate. It operates from 4.75V to 15.5V, delivers rail-to-rail swing into 2kΩ and 600Ω loads, and is used in high-impedance sensor interfaces and medical instrumentation signal conditioning.

For engineers reviewing the LMC662CM datasheet, LMC662CM pinout, LMC662CM application, or LMC662CM equivalent, this page provides verified specifications, SOIC-8 package details, real-world design context for low-leakage circuits, and validated alternative options for precision amplification where input bias current and offset drift are critical.

Technical Context

The LMC662CM uses a proprietary CMOS front-end topology enabling full rail-to-rail output swing while maintaining input common-mode range extending to V− (ground in single-supply mode). Its differential input stage achieves ultra-low input bias current (2fA typ) without compromising voltage gain (≥126dB) or noise performance (22nV/√Hz at 1kHz).

Unlike conventional CMOS op amps, it sustains high open-loop gain under realistic loads: ≥440 V/mV into 2kΩ and ≥220 V/mV into 600Ω at VS = 15V. Its phase margin is 50°, and it supports stable operation with capacitive loads when compensated using series output resistors or pull-up networks per TI's layout guidelines.

Key Specifications

Pinout & Package

LMC662CM is housed in an 8-pin SOIC (D package) with standard dual op amp pinout optimized for single-supply PCB layout and guard ring implementation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision dual operational amplifier applications.

Compared with LMC6062IMX/NOPB and OPA2182IDR, the LMC662CM uniquely balances ultra-low input bias current (2fA), rail-to-rail output, single-supply operation (4.75–15.5V), and 1.1V/μs slew rate - making it the only option among the three suitable for portable, single-supply, high-Z sensor interfaces requiring both DC precision and AC fidelity up to 10kHz.

Availability

LMC662CM is available at Aetrix Electronics and suitable for medical instrumentation, industrial sensor signal conditioning, and portable test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LMC662CM 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 is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision op amp design and manufacturing.

The LMC662CM belongs to TI's LMC66x family of CMOS rail-to-rail op amps, engineered specifically for single-supply, high-impedance applications where ultra-low input bias current and wide common-mode range are essential - such as electrochemical sensors, precision integrators, and battery-powered instrumentation.

FAQ

What is the maximum capacitive load the LMC662CM can drive without oscillation?

The LMC662CM is not inherently stable with large capacitive loads. When driving >100pF, oscillation risk increases-especially in unity-gain follower configurations. TI recommends adding a 50Ω–100Ω series resistor at the output and/or a 5pF–10pF feedback capacitor from output to inverting input. With these measures, stable operation up to ~1nF is achievable. The LMC662CM datasheet Figure 5-14 confirms stability up to 500pF with proper compensation.

Does the LMC662CM support true rail-to-rail input common-mode range?

No-the LMC662CM supports rail-to-rail *output* swing and includes V− in its input common-mode range (i.e., down to ground in single-supply use), but its input does not extend to V+. Per datasheet Section 5.6, the upper limit is (V+) − 1.9V at 25°C. This means with a 5V supply, max input is ~3.1V-not the full 5V rail. So it is rail-to-rail output and ground-swinging input, not full rail-to-rail input.

What is the guaranteed input offset voltage specification for LMC662CM over temperature?

The LMC662CM (LMC662AI grade) guarantees ±3.3mV maximum input offset voltage over the full –40°C to +85°C operating range. At room temperature (25°C), the typical value is ±1mV, with a maximum of ±3mV. This is explicitly specified in Table 5.6 under "OFFSET VOLTAGE" with test condition "TA = –40°C to +85°C".

Can the LMC662CM operate from a 3.3V supply?

No-LMC662CM has a minimum recommended supply voltage of 4.75V per Section 5.3. Operation below 4.75V is outside specifications and may result in degraded rail-to-rail output swing, reduced open-loop gain, increased input bias current, or failure to meet offset and noise specs. For 3.3V systems, consider TI's LMC6482 or OPA333 families instead.

Is LMC662CM pin-compatible with LM358?

Yes-TI explicitly states in Section 6.2 that the LMC662 is pin-for-pin compatible with LM358 in SOIC-8 (D) and PDIP-8 (P) packages. However, note key differences: LMC662CM offers rail-to-rail output and lower input bias current (2fA vs 45nA), but narrower supply range (4.75–15.5V vs LM358's 3–32V) and higher cost. Direct replacement is electrically valid where supply and speed requirements align.