Pin Description Inquiry
Table
| Connection | From Component/Pin | To Component/Pin | Net Label / Note |
|---|---|---|---|
| 1. Power from Battery | Li-ion Battery Connector positive terminal | VIN (input) of the Battery Protection/Charging IC (e.g., BQ24075RGTT) | Label as BAT+ |
| Li-ion Battery Connector negative terminal | Common Ground (GND) | Use a common GND net | |
| 2. Battery Protection Output | Output pin of Battery Protection/Charging IC | Input pin of AMS1117-3.3 | (Net remains “BAT+” through protection; optionally label as PROTECT at the output of the Battery IC) |
| 3. 3.3V Regulation | AMS1117-3.3 Input | From Battery Protection IC output | See step 2 above |
| AMS1117-3.3 Output | Provides regulated 3.3V (Net label: 3V3) | Decoupling: “10 µF” at input; “22 µF” + “0.1 µF” capacitor directly at output | |
| 4. Powering Logic Devices | AMS1117-3.3 3V3 net | All VCC/VDD pins on ESP-12F and ASM330LHHXG1 | Add local 0.1 µF decoupling capacitors as close as possible to each VCC/VDD_IO pin |
| 5. SPI Connections | ESP-12F SPI SCLK | ASM330LHHXG1 SCLK | Route as a short trace; label net as SPI_CLK |
| ESP-12F MOSI | ASM330LHHXG1 MOSI/SDI | Label net as SPI_MOSI | |
| ESP-12F MISO | ASM330LHHXG1 MISO/SDO | Label net as SPI_MISO | |
| ESP-12F CS | ASM330LHHXG1 CS | Label net as SPI_CS (drive low for communication) | |
| 6. Ground Connections | All GND pins on every component | Common Ground (GND) | Ensure a continuous, low-impedance ground plane. |
| 7. Additional External Components | Refer to the BQ24075RGTT datasheet | Add resistor divider and current-sense resistor network, plus input/output filtering capacitors | These support programming of charge current, voltage thresholds, and ensure proper power-path management per the Battery IC datasheet. |