# LM4864MX

**Texas Instruments** · Audio Amplifiers · SOIC-8

LM4864MX from Texas Instruments, in a SOIC-8. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | SHUTDOWN | input | Shutdown control that turns off the amplifier bias circuitry when a logic high is applied (trigger point typically half supply), best tied to VDD or GND and not left floating. |
| 2 | BYPASS | passive | Half-supply (VDD/2) bypass node that connects to external capacitor CB, with 1.0 µF recommended for good click and pop performance and PSRR. |
| 3 | +IN | input | Non-inverting input of the first amplifier. |
| 4 | -IN | input | Inverting input of the first amplifier, where gain is set by Ri and RF with AVD = 2*(RF/Ri). |
| 5 | Vo1 | output | Output of the first amplifier, one side of the bridged load. |
| 6 | VDD | power_in | Positive supply, operating range 2.7V to 5.5V (6.0V absolute max), with a 0.1 µF bypass capacitor. |
| 7 | GND | power_in | Ground. |
| 8 | Vo2 | output | Output of the second amplifier (fixed unity-gain inverting), the other side of the bridged load, 180° out of phase with Vo1. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-8 |
| Category | Amplifiers/Comparators |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `LM4864MX`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `lm4864mx-etched.step` / `lm4864mx-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm4864mx.step` / `lm4864mx.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/lm4864) (29 pp, sha256 `8e340227e33ea6b4`, retrieved 2026-10-11, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/lm4864mx-datasheet.pdf)