# HX4055M

**HX(hengjiaxing)** · Battery Management ICs · SOT-23-5

HX4055M from HX(hengjiaxing), in a SOT-23-5. 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 | CHRG | output | Open-drain charge status output that is pulled low while charging and is high-impedance otherwise (sinks up to 10mA to drive an LED; absolute max -0.3V to 10V). |
| 2 | GND | power_in | Ground. |
| 3 | BAT | power_out | Charge current output to the battery, with a 4.2V (±1%) float voltage and a maximum pin current of 500mA. |
| 4 | VCC | power_in | Positive input supply voltage, operating range 4.0V to 9.0V (absolute max -0.3V to 9V), with undervoltage lockout threshold of 3.6V typical. |
| 5 | PROG | bidirectional | Charge current programming, charge current monitor and shutdown pin: a resistor to ground sets the charge current, leaving it floating shuts down the charger (absolute max -0.3V to VCC+0.3V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HX(hengjiaxing) |
| Package | SOT-23-5 |
| Category | Power Management ICs |
| Pins | 5 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Input supply voltage | VCC | 4 | 5 | 9 | V |  | 3 |
| Input supply current, charge mode | ICC |  | 150 | 500 | uA | Charge mode, RPROG=11K | 3 |
| Input supply current, standby mode | ICC |  | 40 | 100 | uA | Standby mode (charge terminated) | 3 |
| Input supply current, shutdown mode | ICC |  | 40 | 100 | uA | Shutdown mode (RPROG not connected, VCC<VBAT, or VCC<VUV) | 3 |
| Regulated output (float) voltage | VFLOAT | 4.158 | 4.2 | 4.242 | V | 0°C≤TA≤85°C, IBAT=40mA | 3 |
| BAT pin current, current mode | IBAT | 80 | 100 | 120 | mA | RPROG=11K, current mode | 3 |
| BAT pin current, current mode | IBAT | 290 | 310 | 320 | mA | RPROG=3.6K, current mode | 3 |
| BAT pin current, current mode | IBAT | 480 | 500 | 520 | mA | RPROG=2.2K, current mode | 3 |
| Trickle charge current | ITRIKL | 10 | 15 | 20 | mA | VBAT<VTRIKL, RPROG=11K | 3 |
| Trickle charge threshold voltage | VTRIKL | 2.75 | 2.9 | 3 | V | RPROG=11K, VBAT rising | 3 |
| Trickle charge hysteresis voltage | VTRHYS | 60 | 80 | 100 | mV | RPROG=11K | 3 |
| VCC undervoltage lockout threshold | VUV | 3.4 | 3.6 | 3.8 | V | From VCC low to high | 3 |
| VCC undervoltage lockout hysteresis | VUVHYS | 150 | 200 | 300 | mV |  | 3 |
| Manual shutdown threshold voltage, rising | VMSD | 3.4 | 3.5 | 3.6 | V | PROG pin rising | 3 |
| Manual shutdown threshold voltage, falling | VMSD | 1.9 | 2 | 2.1 | V | PROG pin falling | 3 |
| VCC-VBAT lockout threshold voltage, rising | VASD | 60 | 100 | 140 | mV | VCC from low to high | 3 |
| VCC-VBAT lockout threshold voltage, falling | VASD | 5 | 30 | 50 | mV | VCC from high to low | 3 |
| C/10 termination current threshold | ITERM | 8 | 10 | 12 | mV | RPROG=11K | 3 |
| C/10 termination current threshold | ITERM | 30 | 40 | 50 | mV | RPROG=1.66K | 3 |
| PROG pin voltage | VPROG | 0.9 | 1 | 1.1 | V | RPROG=11K, current mode | 3 |
| CHRG pin leakage current | ICHRG | 0 |  | 1 | uA | VCHRG=5V (standby mode) | 3 |
| CHRG pin output low voltage | VCHRG |  | 0.3 | 0.6 | V | ICHRG=5mA | 3 |
| Recharge battery threshold voltage | ΔVRECHRG | 100 | 150 | 200 | mV | VFLOAT-VRECHRG | 3 |
| Junction temperature in thermal limiting | TLIM |  | 120 |  | ℃ |  | 3 |
| Power FET on resistance | RON |  | 650 |  | mΩ | Between VCC and BAT | 3 |
| Soft-start time | tss |  | 20 |  | uS | IBAT=0 to IBAT=1000V/RPROG | 3 |
| Recharge comparator filter time | tRECHARGE | 0.8 | 1.8 | 4 | mS | VBAT high to low | 3 |
| Termination comparator filter time | tTERM | 0.8 | 1.8 | 4 | mS | IBAT falling below ICHG/10 | 3 |
| PROG pin pull-up current | IPROG |  | 2 |  | uA |  | 3 |
| Input supply voltage | VCC | -0.3 |  | 9 | V |  | 2 |
| PROG pin voltage | PROG | -0.3 |  |  | V | -0.3V to VCC+0.3V | 2 |
| BAT pin voltage | BAT | -4.2 |  | 7 | V |  | 2 |
| CHRG pin voltage | CHRG | -0.3 |  | 10 | V |  | 2 |
| BAT pin current | IBAT |  |  | 500 | mA |  | 2 |
| Operating ambient temperature range | TA | -40 |  | 85 | ℃ |  | 2 |
| Storage temperature range | TSTG | -65 |  | 125 | ℃ |  | 2 |

## CAD (KiCad official)

- Symbol: `HX4055M`
- Footprint: `Package_TO_SOT_SMD:SOT-23-5`
- 3D model: SOT-23-5 (KiCad packages3D, STEP)
- 3D model files: `hx4055m-etched.step` / `hx4055m-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `hx4055m.step` / `hx4055m.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HX(hengjiaxing) datasheet](docs/hx4055m-datasheet.pdf) (10 pp, sha256 `3883efda08d1b10d`, retrieved 2026-10-27, 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/hx4055m-datasheet.pdf)