# RT6255AHGJ6F

**Richtek Tech** · DC-DC Converters · TSOT-23-6

RT6255AHGJ6F from Richtek Tech, in a TSOT-23-6. 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 | FB | input | Feedback voltage input used to set the desired output voltage via an external resistive divider (0.6V typ threshold). |
| 2 | EN | input | Enable control input; logic high (min 1.5V) enables the device and connecting to GND (below 0.4V) disables it, abs max rating −0.3V to 20V. |
| 3 | GND | power_in | System ground and power return for the IC. |
| 4 | VIN | power_in | Power input supplying the power switches of the device, operating range 4.5V to 18V. |
| 5 | LX | passive | Switch node that supplies power to the output, connected to the output LC filter inductor; abs max −0.3V to 20V. |
| 6 | BOOT | passive | Bootstrap supply for the high-side gate driver; connect a 0.1µF ceramic capacitor from LX to BOOT. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Richtek Tech |
| Package | TSOT-23-6 |
| Category | Power Supply Chip |
| 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 |
|---|---|---|---|---|---|---|---|
| VIN Supply Input Operating Voltage | VIN | 4.5 |  | 18 | V |  | 8 |
| VIN Under-Voltage Lockout Threshold-Rising | VUVLO | 3.9 | 4.1 | 4.3 | V | VIN rising | 8 |
| EN Input High Voltage | VEN_H | 1.5 |  |  | V |  | 9 |
| EN Input Low Voltage | VEN_L |  |  | 0.4 | V |  | 9 |
| Feedback Threshold Voltage | VTH_FB | 0.594 | 0.6 | 0.606 | V |  | 9 |
| Feedback Current | IFB | -50 |  | 50 | nA | VFB = 4V | 9 |
| Low-Side Switch Valley Current Limit | ILIM_L | 5.25 | 7.25 | 9.25 | A |  | 9 |
| Oscillator Frequency | fSW | 400 | 500 | 600 | kHz |  | 9 |
| Supply Current (Shutdown) | ISHDN |  | 3 |  | µA | VEN = 0 | 8 |
| Supply Current (Quiescent) | IQ |  | 115 |  | µA | IOUT = 0, VFB = VREF x 105% (not switching) | 8 |
| VIN UVLO Hysteresis | VUVLO |  | 0.3 |  | V |  | 8 |
| Soft-Start Time | tSS |  | 1.5 |  | ms |  | 8 |
| High-Side Switch On-Resistance | RDS(ON)_H |  | 45 |  | mΩ | VBOOT − VLX = 4.8V | 9 |
| Low-Side Switch On-Resistance | RDS(ON)_L |  | 23 |  | mΩ |  | 9 |
| High-Side Switch Current Limit | ILIM_H |  | 10.5 |  | A |  | 9 |
| Minimum On-Time | tON_MIN |  | 60 |  | ns | VIN = VIN(MAX) | 9 |
| Minimum Off-Time | tOFF_MIN |  | 200 |  | ns |  | 9 |
| Thermal Shutdown Threshold | TSD |  | 150 |  | °C |  | 9 |
| Thermal Shutdown Hysteresis | TSD |  | 15 |  | °C |  | 9 |
| UVP Trip Threshold |  |  | 60 |  | % | UVP detect | 9 |
| Supply Input Voltage | VIN | 4.5 |  | 18 | V |  | 8 |
| Junction Temperature Range | TJ | -40 |  | 125 | °C |  | 8 |
| Ambient Temperature Range | TA | -40 |  | 85 | °C |  | 8 |
| Supply Input Voltage | VIN | -0.3 |  | 20 | V |  | 8 |
| Enable Pin Voltage | EN | -0.3 |  | 20 | V |  | 8 |
| Switch Node Voltage | LX | -0.3 |  | 20 | V |  | 8 |
| Switch Node Voltage | LX | -5 |  | 27 | V | <20ns | 8 |
| BOOT to LX | VBOOT − VLX | -0.3 |  | 6 | V |  | 8 |
| Other Pins |  | -0.3 |  | 6 | V |  | 8 |
| Power Dissipation | PD |  |  | 1.923 | W | TA = 25°C, TSOT-23-6 (FC) | 8 |
| Junction Temperature | TJ |  |  | 150 | °C |  | 8 |
| Lead Temperature |  |  |  | 260 | °C | Soldering, 10 sec. | 8 |
| Storage Temperature Range |  | -65 |  | 150 | °C |  | 8 |
| ESD Susceptibility HBM |  |  |  | 2 | kV | HBM | 8 |
| Thermal Resistance Junction-to-Ambient | θJA |  | 52 |  | °C/W | TSOT-23-6 (FC) | 8 |
| Thermal Resistance Junction-to-Case | θJC |  | 5 |  | °C/W | TSOT-23-6 (FC) | 8 |

## CAD (KiCad official)

- Symbol: `RT6255AHGJ6F`
- Footprint: `Package_TO_SOT_SMD:TSOT-23-6`
- 3D model: TSOT-23-6 (KiCad packages3D, STEP)
- 3D model files: `rt6255ahgj6f-etched.step` / `rt6255ahgj6f-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `rt6255ahgj6f.step` / `rt6255ahgj6f.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Richtek Tech datasheet](docs/rt6255ahgj6f-datasheet.pdf) (21 pp, sha256 `9851a77a1f4d8bce`, retrieved 2026-10-24, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/rt6255ahgj6f-datasheet.pdf)