# BQ24040DSQT

**Texas Instruments** · Battery Management · WSON-10-EP(2x2)

BQ24040DSQT from Texas Instruments, in a WSON-10-EP(2x2). 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 | IN | power_in | Input power from DC adapter or USB port, rated 3.5V to 28V range with 1μF to 10μF bypass capacitor from IN to VSS. |
| 2 | ISET | input | Programs fast-charge output current via external resistor from ISET to VSS, range 10.8kΩ (50mA) to 540Ω (1000mA). |
| 3 | VSS | power_in | Ground reference terminal; connect exposed thermal pad to VSS and main PCB ground plane. |
| 4 | PRE-TERM | input | Programs current termination threshold (5 to 50% of ISET fast-charge current) and pre-charge current via external 1kΩ to 10kΩ resistor. |
| 5 | PG | output | Power good indicator open-drain output; pulls low when input voltage above UVLO and exceeds battery output voltage. |
| 6 | NC | unconnected | Not connected; reserved for internal IC use only, do not route through this terminal. |
| 7 | ISET2 | input | Three-state programming input for input/output current limit: low selects ISET, high selects 500mA maximum (BQ24040/5), float selects 100mA maximum. |
| 8 | CHG | output | Charge status open-drain output; pulls low during first charge cycle only, open drain when charging complete or disabled. |
| 9 | TS | input | Temperature sense terminal for 10kΩ NTC thermistor JEITA monitoring, pull low to disable charger, float high to enable TTDM mode, connect 10kΩ resistor to VSS if not used. |
| 10 | OUT | power_out | Battery connection and system load output terminal supporting up to 1.25A continuous current with 1μF to 10μF bypass capacitor from OUT to VSS. |
| 11 | EP | passive | Exposed pad (from the footprint; not named in the datasheet pin table). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | WSON-10-EP(2x2) |
| Category | Power Management (PMIC) |
| Pins | 11 |

## CAD (KiCad official)

- Symbol: `BQ24040DSQT`
- Footprint: `Package_DFN_QFN:Texas_DSQ0010A_WSON-10-1EP_2x2mm_P0.4mm_EP0.9x1.5mm`
- 3D model: WSON-10-EP(2x2) (KiCad packages3D, STEP)
- 3D model files: `bq24040dsqt-etched.step` / `bq24040dsqt-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bq24040dsqt.step` / `bq24040dsqt.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/bq24040) (41 pp, sha256 `02b98f26a3a33997`, retrieved 2026-09-24, 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 0.2`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-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/bq24040dsqt-datasheet.pdf)