# TC6291C

**Shenzhen Fuman** · DC-DC Converters · SOT-23-6

TC6291C from Shenzhen Fuman, in a SOT-23-6. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | LX | output | Switching node - drain of the internal 0.2Ω, 2A, 16V N-channel power MOSFET. Connects to the boost inductor and Schottky rectifier cathode. Absolute max voltage 16V. |
| 2 | GND | power_in | IC ground return for the internal MOSFET source, control logic and current-sense amplifier. Should tie directly to the ground plane close to CIN/COUT. |
| 3 | FB | input | Inverting input of the error amplifier. Connect to the mid-point of the output resistor divider; regulation target Vref = 0.6V (±2%). VOUT = 0.6V × (1 + R1/R2). Absolute max 6V. |
| 4 | EN | input | Enable input, active high. VEN ≥ 0.96V turns the converter on; VEN ≤ 0.6V shuts it down (IQ ≈ 0.1µA). Absolute max 6V. |
| 5 | VCC | power_in | IC supply input. Operating range 2.6V to 5.5V, UVLO ≈ 2.2V (0.1V hysteresis). Absolute max 6V. Decouple close to the pin with low-ESR ceramic. |
| 6 | OC | input | Adjustable peak-current-limit programming pin. A resistor from OC to GND (36kΩ-100kΩ) sets the peak switch current from ~1.5A down to 0.5A per IOCP = 55000/R. Leaving OC floating gives the default (~2A typ, 2.6A max) internal limit. Do not add capacitance on this pin. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shenzhen Fuman |
| Package | SOT-23-6 |
| Category | PMIC |
| Pins | 6 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Supply voltage (absolute maximum) | Vcc | 0 |  | 6 | V |  | 2 |
| LX voltage (absolute maximum) | Vlx | 0 |  | 16 | V |  | 2 |
| EN, FB voltage (absolute maximum) |  | 0 |  | 6 | V |  | 2 |
| Operating temperature | Top | -40 |  | 85 | ℃ |  | 2 |
| Storage temperature | Tst | -65 |  | 150 | ℃ |  | 2 |
| Input voltage range | Vcc | 2.6 |  | 5.5 | V |  | 6 |
| Oscillator frequency | Fosc | 0.8 | 1 | 1.2 | MHz | Vfb=1.0V | 6 |
| Reference voltage | Vref | 0.588 | 0.6 | 0.612 | V |  | 6 |
| Open-circuit current limit | Locp | 2 |  | 2.6 | A |  | 6 |
| Adjustable open-circuit current limit | Locp | 0.5 |  | 1.5 | A | External resistor 36K~100K | 6 |
| Junction temperature | Tj |  |  | 150 | ℃ |  | 2 |
| Power dissipation | Pd |  |  | 455 | mW | SOT23-6 @ Ta=25℃ | 2 |
| Thermal resistance, junction to ambient | θJA |  |  | 220 | ℃/W | SOT23-6 | 2 |
| Lead soldering temperature |  |  |  | 260 | ℃ | Soldering, 10 s | 2 |
| UVLO threshold | Vuvlo |  | 2.2 |  | V |  | 6 |
| UVLO hysteresis (low-voltage shutdown) |  |  | 0.1 |  | V |  | 6 |
| Quiescent current | Icc |  | 0.17 |  | mA | VFB=0.66V, no switching | 6 |
| Supply current with switching | Icc |  | 1.9 |  | mA | VFB=0.55V, with switching | 6 |
| Shutdown current | Icc |  | 0.1 |  | uA | Ven=GND | 6 |
| Frequency variation with voltage | ∆f/∆v |  | 5 |  | % | Vcc=2.6V~5.5V | 6 |
| Maximum duty cycle | Tduty |  | 90 |  | % |  | 6 |
| Reference voltage line regulation |  |  | 0.05 |  | %/V | Vcc=2.6V~5.5V | 6 |
| Enable voltage | Ven |  | 0.96 |  | V |  | 6 |
| Disable voltage | Ven |  | 0.6 |  | V |  | 6 |
| MOSFET on-resistance | Rds(on) |  | 0.2 |  | Ω | Llx=2A | 6 |
| Overtemperature protection threshold | Totp |  | 150 |  | ℃ |  | 6 |

## CAD (KiCad official)

- Symbol: `TC6291C`
- Footprint: `Package_TO_SOT_SMD:SOT-23-6`
- 3D model: SOT-23-6 (KiCad packages3D, STEP)
- 3D model files: `tc6291c-etched.step` / `tc6291c-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `tc6291c.step` / `tc6291c.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`tc6291c.step`](tc6291c.step) | 97 KB | You want the bare part, or you mark your own boards. |
| [`tc6291c-etched.step`](tc6291c-etched.step) | 1.6 MB | You want the part with `TC6291C` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 374 faces against 117 in the bare model. It
survives export, section views, and rendering in any CAD tool, and it drops straight
into KiCad or Fusion with no extra setup.

## Provenance

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

- **Datasheet:** [Shenzhen Fuman datasheet](docs/tc6291c-datasheet.pdf) (10 pp, sha256 `bc0dc73401217660`, retrieved 2026-08-17, 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:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/tc6291c-datasheet.pdf)