HX7544

HX hengjiaxing · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23

HX7544 from HX hengjiaxing, in a SOT-23. 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	Chip ground terminal (芯片接地端); the datasheet gives no separate electrical limit for this pin.
2	VOUT	power_out	Regulated output; for the HX7544 (4.4 V nominal) the output current is at least 60 mA (100 mA typical) and the dropout is 100 mV typical at 1 mA load.
3	VIN	power_in	Input (start-up input) terminal; maximum input voltage is 18 V in operation, with a 20 V absolute maximum rating.

Key specifications

Parameter	Value
Manufacturer	HX hengjiaxing
Package	SOT-23
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 (4.4 V variant)	VOUT	4.268	4.4	4.532	V	VIN＝6V，IOUT＝1mA	3
Output current	IOUT	60	100		mA	VIN＝6.4V	3
Load regulation	ΔVOUT		60	150	mV	VIN＝6.4V，1mA≤IOUT≤30mA	3
Quiescent current	ISS		2	3	µA	VIN＝6.4V，空载	3
Input voltage	VIN			18	V		3
Maximum input voltage	VIN			20	V		2
Power dissipation	PD			200	mW		2
Operating temperature	Tw	-25		70	℃		2
Storage temperature	Tc	-50		125	℃		2
Soldering temperature	Th			260	℃	10s	2
Output voltage tolerance (product selection table)		-3		3	%	Printed as +3% in the model selection table for the output voltage	1
Dropout voltage	VDIF		100		mV	IOUT＝1mA	3
Line regulation	ΔVOUT /(ΔVIN * VOUT)		0.2		％/V	5.4V≤VIN≤18V，IOUT＝1mA	3
Output voltage temperature coefficient	ΔVOUT /ΔTa		0.7		mV/℃	VIN＝6.4V，IOUT＝10mA，0℃≤Ta≤70℃	3

CAD (KiCad official)

Symbol: HX7544
Footprint: Package_TO_SOT_SMD:SOT-23
3D model: SOT-23 (KiCad packages3D, STEP)
3D model files: hx7544-etched.step / hx7544-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); hx7544.step / hx7544.glb are the bare package body.

Provenance

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

Datasheet: HX hengjiaxing datasheet (9 pp, sha256 a346bc691aa07bf5, retrieved 2026-10-19, 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

# HX7544

**HX hengjiaxing** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23

HX7544 from HX hengjiaxing, in a SOT-23. 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 | Chip ground terminal (芯片接地端); the datasheet gives no separate electrical limit for this pin. |
| 2 | VOUT | power_out | Regulated output; for the HX7544 (4.4 V nominal) the output current is at least 60 mA (100 mA typical) and the dropout is 100 mV typical at 1 mA load. |
| 3 | VIN | power_in | Input (start-up input) terminal; maximum input voltage is 18 V in operation, with a 20 V absolute maximum rating. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HX hengjiaxing |
| Package | SOT-23 |
| 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 (4.4 V variant) | VOUT | 4.268 | 4.4 | 4.532 | V | VIN＝6V，IOUT＝1mA | 3 |
| Output current | IOUT | 60 | 100 |  | mA | VIN＝6.4V | 3 |
| Load regulation | ΔVOUT |  | 60 | 150 | mV | VIN＝6.4V，1mA≤IOUT≤30mA | 3 |
| Quiescent current | ISS |  | 2 | 3 | µA | VIN＝6.4V，空载 | 3 |
| Input voltage | VIN |  |  | 18 | V |  | 3 |
| Maximum input voltage | VIN |  |  | 20 | V |  | 2 |
| Power dissipation | PD |  |  | 200 | mW |  | 2 |
| Operating temperature | Tw | -25 |  | 70 | ℃ |  | 2 |
| Storage temperature | Tc | -50 |  | 125 | ℃ |  | 2 |
| Soldering temperature | Th |  |  | 260 | ℃ | 10s | 2 |
| Output voltage tolerance (product selection table) |  | -3 |  | 3 | % | Printed as +3% in the model selection table for the output voltage | 1 |
| Dropout voltage | VDIF |  | 100 |  | mV | IOUT＝1mA | 3 |
| Line regulation | ΔVOUT /(ΔVIN * VOUT) |  | 0.2 |  | ％/V | 5.4V≤VIN≤18V，IOUT＝1mA | 3 |
| Output voltage temperature coefficient | ΔVOUT /ΔTa |  | 0.7 |  | mV/℃ | VIN＝6.4V，IOUT＝10mA，0℃≤Ta≤70℃ | 3 |

## CAD (KiCad official)

- Symbol: `HX7544`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `hx7544-etched.step` / `hx7544-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `hx7544.step` / `hx7544.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HX hengjiaxing datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588904391272882176) (9 pp, sha256 `a346bc691aa07bf5`, retrieved 2026-10-19, 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/hx7544-datasheet.pdf)