# WS4508E-5

**WILLSEMI(Will Semicon)** · Battery Management ICs · SOT-23-5L

WS4508E-5 from WILLSEMI(Will Semicon), in a SOT-23-5L. 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 | CHGb | output | Open-drain charge status output that is pulled low while the battery is charging and forced high impedance when the charge cycle is completed or VCC is removed. |
| 2 | GND | power_in | Ground. |
| 3 | BAT | power_out | Charge current output that provides charge current to the battery and regulates the final float voltage to 4.2V. |
| 4 | VCC | power_in | Power supply input, with an absolute maximum of -0.3 to 8V. |
| 5 | PROG | input | Charge current setting, charge current monitor and shutdown pin, with IBAT = (1/RPROG)*1000, and the chip shuts down when the PROG pin is floating. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | WILLSEMI(Will Semicon) |
| Package | SOT-23-5L |
| 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 |
|---|---|---|---|---|---|---|---|
| Supply Voltage | VCC | -0.3 |  | 8 | V |  | 3 |
| PROG Voltage | VPROG | -0.3 |  |  | V | -0.3 to VCC | 3 |
| BAT Voltage | VBAT | -0.3 |  | 8 | V |  | 3 |
| CHGb Voltage | VCHGb | -0.3 |  |  | V | -0.3 to VCC | 3 |
| BAT Pin Current | IBAT |  |  | 600 | mA |  | 3 |
| Power Dissipation Note1 | Pd |  |  | 0.5 | W | 1 in sq pad, 2oz Cu | 3 |
| Power Dissipation Note2 | Pd |  |  | 0.3 | W | minimum recommended pad, 2oz Cu | 3 |
| Junction Temperature | Tj |  |  | 150 | oC |  | 3 |
| Operation Temperature | Top | -45 |  | 85 | oC |  | 3 |
| Storage Temperature | Tsg | -65 |  | 125 | oC |  | 3 |
| Lead Temperature |  |  |  | 260 | oC | Soldering 10s | 3 |
| Thermal Resistance Junction to Ambient Note1 | RJA1 |  |  | 125 | OC/W | 1 in sq pad, 2oz Cu | 3 |
| Thermal Resistance Junction to Ambient Note2 | RJA2 |  |  | 415 | OC/W | minimum recommended pad, 2oz Cu | 3 |
| Charge Mode Supply Current | ISPLYCHRG |  | 650 | 2000 | uA | RPROG=2kΩ | 4 |
| Charge Mode Supply Current | ISPLYCHRG |  | 240 | 2000 | uA | RPROG=10kΩ | 4 |
| Charge Mode Battery Current | IBATCHRG | 450 | 500 | 550 | mA | RPROG=2kΩ | 4 |
| Charge Mode Battery Current | IBATCHRG | 80 | 93 | 110 | mA | RPROG=10kΩ | 4 |
| PROG Pin Voltage | VPROGCHRG | 0.93 | 1 | 1.07 | V | RPROG=2kΩ | 4 |
| Standby Mode Supply Current | ISPLYSTBY |  | 140 | 500 | uA | Charge Terminated | 4 |
| Standby Mode Battery Current | IBATSTBY | 0 | -2.5 | -6 | uA | Charge Terminated | 4 |
| Shutdown Mode Supply Current | ISPLYASD | 20 | 45 | 90 | uA | VCC<VBAT | 4 |
| Shutdown Mode BAT Pin Current | IBATASD | -0.05 |  | 1 | uA | VCC<VBAT; printed ±0.05 ±1 | 4 |
| UVLO Mode Supply Current | ISPLYUVLO | 20 | 45 | 90 | uA | Vcc<VUV | 4 |
| UVLO Mode BAT Pin Current | IBATUVLO | -0.05 |  | 1 | uA | Vcc<VUV; printed ±0.05 ±1 | 4 |
| Shutdown Mode Supply Current | ISPLYSHUT | 20 | 45 | 70 | uA | Rprog not Connected | 4 |
| Manual Shutdown BAT Pin Current | IBATMSD | -0.05 |  | 1 | uA | Vprog=1.3V; printed ±0.05 ±1 | 4 |
| Sleep Mode BAT Pin Current | IBATSLEEP | -0.05 |  | 1 | uA | Vcc=0V; printed ±0.05 ±1 | 4 |
| Float Voltage | VFLOAT | 4.158 | 4.2 | 4.242 | V |  | 4 |
| Trickle Charge Current | ITRIKL | 20 | 50 | 70 | mA | RPROG=2kΩ | 4 |
| Trickle Charge Voltage Threshold | VTRIKL | 2.8 | 2.9 | 3 | V | RPROG=10kΩ | 4 |
| Trickle Charge Voltage Hysteresis | VTRIKL, HYS |  | 100 |  | mV | RPROG=10kΩ | 4 |
| UVLO Threshold | VUVLO | 3.6 | 3.8 | 4 | V | From Vcc Low to High | 4 |
| UVLO Hysteresis | VUVLO, HYS |  | 250 |  | mV |  | 4 |
| Manual Shutdown Threshold Voltage | VMSD |  | 1.2 |  | V | PROG Pin Rising | 4 |
| Manual Shutdown Threshold Voltage | VMSD |  | 1 | 1.3 | V | PROG Pin Falling | 4 |
| Vcc-VBAT Lockout Threshold Voltage | VASD |  | 50 |  | mV | Vcc from Low to High | 4 |
| Vcc-VBAT Lockout Threshold Voltage | VASD |  | 120 |  | mV | Vcc from High to Low | 4 |
| Auto Recharge Battery Voltage | ΔVRECHRG | 100 | 150 | 200 | mV |  | 4 |
| CHGb Pin Output Low Voltage | VCHGb |  | 0.3 | 0.6 | V | ICHGb=5mA | 4 |
| Junction Temperature In Constant Temperature Mode | TLIM |  | 165 |  | oC |  | 4 |
| Power FET ON Resistance | RON |  | 200 |  | mΩ |  | 4 |
| Soft-Start Time | TSS |  | 100 |  | us | RPROG=2kΩ | 4 |
| Recharge Comparator Filter Time | TRECHRG |  | 2 |  | ms |  | 4 |
| Termination Comparator Filter Time | TTERM |  | 1 |  | ms |  | 4 |
| PROG Pin Pull-up Current | IPROG |  | 3 |  | uA |  | 4 |

## CAD (KiCad official)

- Symbol: `WS4508E-5`
- Footprint: `Package_TO_SOT_SMD:SOT-23-5`
- 3D model: SOT-23-5L (KiCad packages3D, STEP)
- 3D model files: `ws4508e-5-etched.step` / `ws4508e-5-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ws4508e-5.step` / `ws4508e-5.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [WILLSEMI(Will Semicon) datasheet](docs/ws4508e-5-datasheet.pdf) (11 pp, sha256 `10d20a4476ef4b1f`, retrieved 2026-10-22, tier: lcsc)
- **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/ws4508e-5-datasheet.pdf)