Texas Instruments LMC6034IMX

Overview

LMC6034IMX from Texas Instruments is a quad CMOS operational amplifier optimized for high-impedance, low-input-bias-current applications. It delivers 126dB open-loop gain into 2kΩ loads, ultra-low 40fA input bias current, and rail-to-rail input common-mode range including V−. It operates from single 5V or dual ±7.5V supplies and is used in medical instrumentation front-ends and precision current-to-voltage conversion.

For engineers reviewing the LMC6034IMX datasheet, LMC6034IMX pinout, LMC6034IMX application, or LMC6034IMX equivalent, key selection criteria include verified 2.3μV/°C offset drift, 22nV/√Hz input voltage noise, 1.1V/μs slew rate, guaranteed operation at –40°C to +85°C, and SOIC-14 package compatibility with standard PCB assembly processes.

Technical Context

The LMC6034IMX employs a proprietary CMOS input stage enabling input common-mode voltage extension to V− while maintaining ultra-low bias current. Its architecture includes an additional gain stage for improved sinking capability-critical for driving 600Ω loads without significant gain collapse.

Unlike conventional op amps, it achieves stable operation with large feedback resistors (>10MΩ) but requires guard-ring layout and capacitive-load compensation (e.g., series output resistor + feedback capacitor) to maintain phase margin above 50° when driving >100pF loads.

Key Specifications

Pinout & Package

LMC6034IMX is supplied in a 14-pin SOIC (D package) with 1.27mm pitch, JEDEC MS-012 compliant, and rated for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad CMOS op amp applications.

Compared with LMC6034IMX, LMC6044IMX trades ultra-low bias current for higher speed, while OPA2277UA/2K5 sacrifices input impedance and rail-to-rail input for lower offset and noise-making LMC6034IMX uniquely suited for high-Z, single-supply, low-drift integrator and transimpedance roles.

Availability

LMC6034IMX is available at Aetrix Electronics and suitable for medical instrumentation, precision sensor interfaces, and low-power data acquisition systems requiring stable component supply across extended production lifecycles.

Supply support for LMC6034IMX 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 over 90 years of innovation in precision analog ICs.

The LMC603x family was designed specifically for high-impedance, low-drift, single-supply instrumentation applications-addressing limitations of legacy bipolar and early CMOS op amps in medical, scientific, and environmental monitoring equipment.

FAQ

What is the maximum capacitive load the LMC6034IMX can drive without oscillation?

The LMC6034IMX is not inherently stable with purely capacitive loads >100pF. When driving such loads, a 50–100Ω series resistor at the output combined with a 5–10pF feedback capacitor from output to inverting input restores phase margin to >50°. This configuration enables reliable operation with up to 1nF loads in unity-gain follower configurations, as confirmed in TI's SNOS609D datasheet Figure 6-3.

Does the LMC6034IMX support true single-supply operation with input signals at ground potential?

Yes. The LMC6034IMX features an input common-mode range that extends to V−, allowing direct connection of grounded sensors or reference points without level-shifting circuitry. At 25°C and VS = 5V, the input range spans from (V−) – 0.1V to (V+) – 1.9V, and remains functional down to (V−) at full –40°C to +85°C temperature range per Section 5.6 of the datasheet.

What is the recommended PCB layout practice to preserve the 40fA input bias current specification of the LMC6034IMX?

To achieve the specified 40fA input bias current, TI mandates guard-ring implementation: a conductive copper ring surrounding each input pad and connected to the same potential (e.g., reference voltage or buffered input), placed on both top and bottom PCB layers. Surface contamination or humidity can elevate leakage to >1pA without this-rendering the ultra-low bias advantage ineffective. Air-wiring input pins is also validated for critical applications.

How does the LMC6034IMX perform when driving a 600Ω load compared to a 2kΩ load?

LMC6034IMX maintains 100V/mV minimum open-loop gain into 600Ω loads (vs. 200V/mV into 2kΩ), confirming robust drive capability. Output swing degrades predictably: at VS = 15V, it delivers 12.0V to 13.9V positive swing and 0.79V to 1.75V negative swing into 600Ω-sufficient for most instrumentation interfaces. Sinking gain drops more than sourcing under heavy load, per Table 5-6 electrical characteristics.

Is the LMC6034IMX pin-compatible with other TI quad op amps like the LM324 or TLV2464?

No. LMC6034IMX uses a unique pinout optimized for its quad architecture: V+ is on Pin 4 and V− on Pin 11, differing from LM324 (V+ on Pin 4, V− on Pin 11 only in some variants) and TLV2464 (V+ on Pin 14, V− on Pin 3). Direct replacement requires PCB redesign. However, LMC6034IMX is functionally compatible with LMC6032 (dual version) in shared design platforms where channel count permits.