# BL4056C-42ES

**BL(Shanghai Belling)** · Battery Management ICs · ESOP-8

BL4056C-42ES from BL(Shanghai Belling), in a ESOP-8. 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 | TEMP | input | Battery temperature sense input: the NTC divider voltage is compared with internal thresholds VLOW = 45%×VCC and VHIGH = 80%×VCC, charging pauses when VTEMP is outside that window, and tying TEMP to GND disables temperature monitoring; absolute maximum is -0.3 V to 10 V. |
| 2 | PROG | bidirectional | Sets the constant-charge current through a resistor to GND (IBAT = 1100 / RPROG, for example 1.1 kΩ gives 1000 mA, ±10%) and monitors the charge current with about 1.0 V on the pin in current mode; absolute limits are -0.3 V to VCC+0.3 V and 1200 µA pin current. |
| 3 | GND | power_in | Ground pin; the PROG current-set resistor and the TEMP divider network return to this pin. |
| 4 | VCC | power_in | Input supply pin with a specified operating range of 4.2 V to 9.0 V (5 V typical) and absolute range of -6.5 V to 9 V; undervoltage lockout threshold is 3.6 V and adaptive current reduction starts at 4.3 V. |
| 5 | BAT | power_out | Charger output to the single Li-ion cell, with a float voltage of 4.2 V for the BL4056C-42ES variant, absolute limits of -4.35 V to 7 V, and a pin current rating of 1200 mA. |
| 6 | STDBY | output | Open-drain charge-complete status output that is pulled low when charging is finished, with output low of 0.3 V to 0.6 V at 5 mA and absolute maximum of -0.3 V to 10 V. |
| 7 | CHRG | output | Open-drain charging status output that is pulled low while the battery is charging and is high-impedance otherwise, with output low of 0.3 V to 0.6 V at 5 mA and absolute maximum of -0.3 V to 10 V. |
| 8 | CE | input | Chip-enable input: driving it low stops charging and places the device in shutdown, with an absolute range of -6.5 V to 10 V. |
| 9 | EP | passive | Exposed pad (from the footprint; not named in the datasheet pin table). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | BL(Shanghai Belling) |
| Package | ESOP-8 |
| Category | Power Management ICs |
| Pins | 9 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| 输入电源电压 (VCC) - supply voltage | VCC | 4.2 | 5 | 9 | V |  | 3 |
| 输入电源电流 - charge mode | ICC |  | 150 | 500 | μA | 充电模式，RPROG=1.1K | 3 |
| 输入电源电流 - standby (charge terminated) | ICC |  | 70 | 120 | μA | 待机模式（充电终止） | 3 |
| 输入电源电流 - shutdown | ICC |  | 70 | 120 | μA | 停机模式（RPROG未连，VCC<VBAT，或 VCC<VUV） | 3 |
| 稳定输出（浮充）电压 - 4.2V version | VFLOAL | 4.158 | 4.2 | 4.242 | V | 0℃≤TA≤85℃ | 3 |
| BAT pin current - current mode | IBAT | 450 | 500 | 550 | mA | 电流模式测试 VBAT=4.0V，RPROG=2.2K | 3 |
| BAT pin current - current mode | IBAT | 950 | 1000 | 1060 | mA | 电流模式测试 VBAT=4.0V，RPROG=1.1K | 3 |
| BAT pin current - standby | IBAT | -2 |  | -1 | μA | 待机模式，VBAT=VFLOAL | 3 |
| BAT pin current - shutdown | IBAT | -6 |  | -2 | μA | 停机模式（RPROG未连） | 3 |
| 涓流充电电流 - trickle charge current | ITRIKL | 200 | 230 | 260 | mA | VBAT<VTRIKL，RPROG=1.1K | 3 |
| 涓流充电门限电压 - trickle charge threshold | VTRIKL | 2.8 | 2.9 | 3 | V | RPROG=1.1K，VBAT上升 | 3 |
| 涓流充电迟滞电压 - trickle charge hysteresis | VTRHYS | 60 | 80 | 100 | mV | RPROG=1.1K | 3 |
| VCC欠压闭锁迟滞 - UVLO hysteresis | VUVHYS | 150 | 200 | 300 | mV |  | 3 |
| VCC-VBAT闭锁门限电压 - VCC low to high | VASD | 60 | 100 | 140 | mV | VCC从低到高 | 3 |
| VCC-VBAT闭锁门限电压 - VCC high to low | VASD | 5 | 30 | 50 | mV | VCC从高到低 | 3 |
| C/10 终止电流门限 - termination current | ITERM | 60 | 70 | 80 | mA | RPROG=2.4K | 3 |
| C/10 终止电流门限 - termination current | ITERM | 120 | 130 | 140 | mA | RPROG=1.1K | 3 |
| PROG 引脚电压 - PROG pin voltage | VPROG | 0.9 | 1 | 1.1 | V | RPROG=1.1K，电流模式 | 3 |
| CHRG 引脚输出低电压 - CHRG output low voltage | VCHRG |  | 0.3 | 0.6 | V | CHRG I =5mA | 3 |
| STDBY 引脚输出低电平 - STDBY output low voltage | VSTDBY |  | 0.3 | 0.6 | V | STDBY I =5mA | 3 |
| TEMP 引脚高端翻转电压 - TEMP high threshold | VTEMP-H | 80 | 82 |  | %VCC |  | 3 |
| TEMP 引脚低端翻转电压 - TEMP low threshold | VTEMP-L | 43 | 45 |  | %VCC |  | 3 |
| 再充电电池门限电压 - recharge threshold | ΔVRECHRG | 80 | 110 | 140 | mV | VFLOAT-VRECHRG | 3 |
| 再充电比较器滤波时间 - recharge comparator filter time | tRECHARGE | 0.8 | 2 | 4 | ms | VBAT高至低 | 3 |
| 终止比较器滤波时间 - termination comparator filter time | tTERM | 0.8 | 2 | 4 | ms | IBAT降至 ICHG/10 以下 | 3 |
| VIN 反向漏电流 - reverse leakage on VIN | IVIN |  | 10 | 20 | uA | VIN 端反接，VBAT=VFLOAT | 3 |
| 电池反向漏电流 - reverse leakage on battery | IBAT |  | 2.5 | 5 | mA | 电池反接，VIN=5V | 3 |
| 输入电源电压（VCC）- absolute max | VCC | -6.5 |  | 9 | V |  | 1 |
| PROG 引脚电压 - absolute max | PROG | -0.3 |  |  | V | max printed as VCC+0.3V | 1 |
| BAT 引脚电压 - absolute max | BAT | -4.35 |  | 7 | V |  | 1 |
| CHRG 引脚电压 - absolute max | CHRG | -0.3 |  | 10 | V |  | 1 |
| STDBY 引脚电压 - absolute max | STDBY | -0.3 |  | 10 | V |  | 1 |
| TEMP 引脚电压 - absolute max | TEMP | -0.3 |  | 10 | V |  | 1 |
| CE 引脚电压 - absolute max | CE | -6.5 |  | 10 | V |  | 1 |
| BAT 引脚电流 - absolute max | IBAT |  |  | 1200 | mA |  | 1 |
| PROG 引脚电流 - absolute max | IPROG |  |  | 1200 | uA |  | 1 |
| 最大结温 - maximum junction temperature | TJ |  |  | 145 | ℃ |  | 1 |
| 贮存温度范围 - storage temperature | TSTG | -65 |  | 125 | ℃ |  | 1 |
| 引脚温度（焊接）- lead temperature | TLEAD |  |  | 260 | ℃ | 焊接时间10秒 | 1 |
| 工作环境温度范围 - operating ambient temperature |  | -40 |  | 85 | ℃ |  | 1 |

## CAD (KiCad official)

- Symbol: `BL4056C-42ES`
- Footprint: `Package_SO:SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.41x3.3mm`
- 3D model: ESOP-8 (KiCad packages3D, STEP)
- 3D model files: `bl4056c-42es-etched.step` / `bl4056c-42es-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bl4056c-42es.step` / `bl4056c-42es.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [BL(Shanghai Belling) datasheet](docs/bl4056c-42es-datasheet.pdf) (12 pp, sha256 `a6c827c4c83b84ee`, retrieved 2026-11-05, 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/bl4056c-42es-datasheet.pdf)