# LM34927MR

**Texas Instruments** · DC-DC Converters · SO-8

LM34927MR from Texas Instruments, in a SO-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 | RTN | power_in | Ground connection of the integrated circuit; the exposed pad must be connected to this pin. |
| 2 | VIN | power_in | Input voltage with an operating input range of 7.5 V to 100 V; the RON resistor connects between this pin and RON to set on-time. |
| 3 | UVLO | input | Input to the undervoltage comparator; a resistor divider from VIN to UVLO to GND sets the undervoltage threshold, and pulling it below 0.66 V externally puts the part in shutdown. |
| 4 | RON | input | On-time control; a resistor between this pin and VIN sets the switch on-time as a function of VIN, with a minimum recommended on-time of 100 ns at maximum input voltage. |
| 5 | FB | input | Feedback pin connected to the inverting input of the internal regulation comparator, with a regulation level of 1.225 V. |
| 6 | VCC | power_out | Output of the internal high-voltage series pass regulator, regulated at 7.6 V, which biases the gate drivers and internal circuitry and requires a 1.0 µF decoupling capacitor. |
| 7 | BST | input | Bootstrap pin; a 0.01 µF ceramic capacitor is required between BST and SW, charged by VCC through an internal diode when SW is low. |
| 8 | SW | output | Power switching node that connects to the output inductor and the bootstrap capacitor. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SO-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `LM34927MR`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SO-8 (KiCad packages3D, STEP)
- 3D model files: `lm34927mr-etched.step` / `lm34927mr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm34927mr.step` / `lm34927mr.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/lm34927) (34 pp, sha256 `d9409c664f8b501b`, retrieved 2026-10-08, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/lm34927mr-datasheet.pdf)