# A6271KLPTR-T

**Allegro MicroSystems, LLC** · LED Drivers · TSSOP-16-EP

A6271KLPTR-T from Allegro MicroSystems, LLC, in a TSSOP-16-EP. 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 | COMP | passive | Compensation pin for output of GM error amplifier. |
| 2 | IREF | input | Analog dimming input; a capacitor on this pin provides a soft-start period when coming out of sleep mode. |
| 3 | FAULTn | output | Open drain output; logic low indicates detection of a fault such as LED overload, output undervoltage or overvoltage, input supply undervoltage, or VREG undervoltage. |
| 4 | OSC | input | Oscillator input for setting switching frequency and for external synchronization. |
| 5 | DITH | passive | Dither frequency range set; connect a resistor from this pin to GND, or connect to VREG if not used. |
| 6 | DR | input | A voltage applied to this pin programs the duty cycle of PWM internal mode. |
| 7 | PWMIN | input | Used for putting the device into sleep mode or analog dimming control, and can also be used for external or internal PWM control. |
| 8 | VREG | power_out | 5 V regulator output; connect a filter capacitor from VREG to GND. |
| 9 | SG | output | Switch gate drive output. |
| 10 | SP | input | Switch current sense and slope compensation input. |
| 11 | GND | power_in | Ground. |
| 12 | OVUV | input | Programmable-output overvoltage and undervoltage protection input. |
| 13 | PWMOUT | output | PWM gate drive for external p-channel MOSFET, active low. |
| 14 | LN | input | LED current sense negative input. |
| 15 | LP | input | LED current sense positive input. |
| 16 | VIN | power_in | Main supply input; absolute maximum rating is -0.3 to 55 V with respect to GND. |
| 17 | EP | passive | Exposed pad (from the footprint; not named in the datasheet pin table). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Allegro MicroSystems, LLC |
| Package | TSSOP-16-EP |
| Category | Nixie Tube Driver/LED Driver |
| Pins | 17 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts | copper |  | The drain connection of the switching MOSFET, PWM MOS￾FET, and cathode terminal of the recirculation diode are used for thermal heatsinking. It is advised to use sufficient copper around | 20 |

## CAD (KiCad official)

- Symbol: `A6271KLPTR-T`
- Footprint: `Package_SO:TSSOP-16-1EP_4.4x5mm_P0.65mm`
- 3D model: TSSOP-16-EP (KiCad packages3D, STEP)
- 3D model files: `a6271klptr-t-etched.step` / `a6271klptr-t-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `a6271klptr-t.step` / `a6271klptr-t.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Allegro MicroSystems, LLC datasheet](docs/a6271klptr-t-datasheet.pdf) (37 pp, sha256 `054f63abc640cd41`, retrieved 2026-10-28, tier: lcsc)
- **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/a6271klptr-t-datasheet.pdf)