# HT7550A-1Q

**QNH** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-92

HT7550A-1Q from QNH, in a TO-92. 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 | GND | power_in | Ground reference; the output needs a capacitor of more than 2.2µF from VOUT to ground. |
| 2 | VIN | power_in | Regulator input, rated to a maximum of 24V (absolute maximum -0.3 to +24V); place the input capacitor close to this pin. |
| 3 | VOUT | power_out | Regulated 5.0V output (±2%) for the HT7550, with 100mA minimum output current at VIN=VOUT+2.0V; place the output capacitor close to this pin. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | QNH |
| Package | TO-92 |
| Category | Power Management (PMIC) |
| Pins | 3 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output voltage | VOUT | 4.9 | 5 | 5.1 | V | VIN=VOUT+2.0V, IOUT=10mA | 9 |
| Output current | IOUT | 100 | 150 |  | mA | VIN=VOUT+2.0V | 9 |
| Load regulation | ΔVOUT |  | 5 | 60 | mV | VIN=VOUT+2.0V, 1mA≤IOUT≤70mA | 9 |
| Dropout voltage | VDIF |  | 25 | 55 | mV | IOUT=1mA, ΔVOUT=2% | 9 |
| Quiescent current | ISS |  | 1.5 | 3 | μA | No load | 9 |
| Line regulation | ΔVOUT/(VOUT*ΔVIN) |  |  | 0.2 | %/V | VOUT+1.0V≤VIN≤24V, IOUT=1mA | 9 |
| Input voltage | VIN |  |  | 24 | V |  | 9 |
| Output voltage temperature coefficient | ΔVOUT/(ΔTA*VOUT) |  | 100 |  | ppm/°C | VIN=VOUT+2.0V, IOUT=10mA, -40℃≤TA≤85℃ | 9 |
| Input voltage (absolute maximum) | VIN | -0.3 |  | 24 | V |  | 4 |
| Storage temperature | TSTG | -50 |  | 125 | ℃ |  | 4 |
| Operating temperature | TA | -40 |  | 85 | ℃ |  | 4 |
| Thermal resistance | θJA |  |  | 200 | ℃/W | TO92 | 4 |
| Power dissipation | PD |  |  | 500 | mW | TO92 | 4 |

## CAD (KiCad official)

- Symbol: `HT7550A-1Q`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92 (KiCad packages3D, STEP)
- 3D model files: `ht7550a-1q-etched.step` / `ht7550a-1q-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ht7550a-1q.step` / `ht7550a-1q.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [QNH datasheet](docs/ht7550a-1q-datasheet.pdf) (13 pp, sha256 `78e25abc675b4c05`, retrieved 2026-10-22, 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-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/ht7550a-1q-datasheet.pdf)