Texas Instruments LMC6009MTX

Overview

LMC6009MTX from Texas Instruments (formerly National Semiconductor) is a 9-channel CMOS unity-gain buffer IC designed specifically for gamma voltage buffering in TFT-LCD column driver circuits. It delivers 80 mA short-circuit output current per channel, operates from 2.7 V to 5.5 V, features A/B dual-input switching for asymmetric gamma correction, and guarantees stable operation into 96 nF capacitive loads with 3 µs settling time.

For engineers reviewing the LMC6009MTX datasheet, LMC6009MTX pinout, LMC6009MTX application, or LMC6009MTX equivalent, key selection criteria include its 9 independent high-current buffers, dual gamma input architecture, TSSOP-48 package compatibility, thermal shutdown protection, and guaranteed performance across −20°C to +75°C for display timing-critical systems.

Technical Context

The LMC6009MTX integrates nine rail-to-rail output buffers with matched gain (0.985 V/V) and separate A/B differential input pairs per channel - enabling dynamic gamma reference selection during row inversion. Its output stage is optimized for capacitive loading up to 96 nF while maintaining stability without external compensation.

Each buffer supports bidirectional 13–20 mA sourcing/sinking depending on supply voltage (3 V or 5 V), with output voltage swing specified as VDD–0.2 V (high) and GND+0.2 V (low) under load. The single A/B control input (Pin 29) selects between two gamma reference strings, eliminating discrete multiplexing circuitry in TFT-LCD gamma calibration paths.

Key Specifications

Pinout & Package

LMC6009MTX is housed in a 48-pin Thin Shrink Small Outline Package (TSSOP), JEDEC standard MTD48, with 0.5 mm pitch and exposed thermal pad (not electrically connected). Pin 1 is located at top-left corner with dot marking; pins are numbered counter-clockwise.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar gamma buffer applications.

Compared with LMC6009MTX, LMC6001MTX offers channel-level flexibility but increases component count and layout complexity, while MAX4473EEE+ lacks the integrated A/B multiplexing essential for modern row-inverted TFT-LCDs - making LMC6009MTX the only solution that simultaneously delivers 9-channel buffering, dual gamma support, and TSSOP-48 integration.

Availability

LMC6009MTX is available at Aetrix Electronics and suitable for VGA/SVGA TFT-LCD drive circuits, electronic notebooks, and personal digital assistants requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LMC6009MTX 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 (TI) acquired National Semiconductor in 2011 and maintains full technical and manufacturing continuity for legacy analog products including the LMC series.

The LMC6009MTX belongs to TI's legacy display interface portfolio, engineered specifically for gamma voltage buffering in cost-sensitive, high-volume TFT-LCD modules used in portable consumer electronics.

FAQ

What is the primary function of the LMC6009MTX in a TFT-LCD system?

The LMC6009MTX serves as a 9-channel unity-gain buffer that conditions and distributes gamma correction reference voltages to column drivers in TFT-LCD panels. It enables dynamic A/B gamma switching during row inversion, sources up to 200 mA per channel at 5 V, and ensures fast settling (<3 µs) into large capacitive loads - directly improving grayscale fidelity and reducing motion artifacts in VGA/SVGA displays.

Does the LMC6009MTX support both 3.3 V and 5 V supply rails?

Yes, the LMC6009MTX is fully specified for operation from 2.7 V to 5.5 V DC. Electrical characteristics are guaranteed at both 3.0 V and 5.0 V supply voltages, including output voltage swing (VDD–0.2 V high, GND+0.2 V low), settling time (3 µs typ), and short-circuit current (80 mA min at 3 V, 120 mA min at 5 V), making it compatible with mixed-voltage display subsystems.

How does the A/B switching feature of the LMC6009MTX improve display performance?

The A/B switching feature in the LMC6009MTX allows real-time selection between two independent gamma reference strings via a single logic input (Pin 29), compensating for asymmetrical gamma shifts caused by row inversion in TFT-LCDs. This eliminates the need for external analog switches or multiplexers, reduces timing skew between channels, and maintains consistent grayscale tracking across frame boundaries - critical for high-fidelity video playback.

What is the significance of the three separate VDD and GND pins on the LMC6009MTX?

The LMC6009MTX uses three dedicated VDD (Pins 30, 38, 44) and three GND (Pins 31, 37, 43) terminals to isolate power domains for different buffer groups - minimizing supply noise coupling and crosstalk between adjacent gamma channels. This partitioning improves PSRR and ensures stable, low-distortion output performance in high-density LCD panel layouts where shared supply paths would degrade gamma accuracy.

Is thermal shutdown protection active in the LMC6009MTX, and how does it behave?

Yes, the LMC6009MTX includes built-in thermal shutdown protection that activates when junction temperature exceeds approximately 150°C. Upon activation, output stages disable to prevent damage; recovery occurs automatically once die temperature falls below the hysteresis threshold (~140°C). This safeguard is essential during sustained high-current drive conditions in compact notebook or PDA enclosures with limited airflow.