SLUSE53 December 2024 BQ25751
PRODUCTION DATA
請參考 PDF 數據表獲取器件具體的封裝圖。
The battery current sense resistor between SRP and SRN is fixed at 5 mΩ; using a different value is not recommended. The input current sense resistor between ACP and ACN is typically 2 mΩ, but can be changed to 5 mΩ. In USB-PD applications, a 5-mΩ sense resistor is recommended to achieve programmability in 50 mA/step whereas for power-path applications, a 2 mΩ sense resistor is preferred. In addition, if input current limit function is not desired, ACP and ACN may be shorted together. For both of these sense resistors, a filter network is recommended as shown in the Typical Application.
For both the input current and the output current, the limits may be programmed using the I2C interface or an external programming resistor on ILIM_HIZ and ICHG pins, respectively.
| PARAMETER | FORMULA | VALUE |
|---|---|---|
| Input Current Hardware Limit | RILIM_HIZ = KILIM / 20 A | 2.5 kΩ for 20 A with 2-mΩ RAC_SNS |
| Output Current Hardware Limit | RICHG = KICHG / 10 A | 5 kΩ for 10 A with 5-mΩ RBAT_SNS |
The default input sense resistor (RAC_SNS) is 2 mΩ, and the register allows for a range of up-to 50-A input current limit.If a 5-mΩ RAC_SNS is used, and the register is programmed to a value of 0x60, the true maximum current across the RAC_SNS will be: 50A * 2/5 = 20 A. With a 5-mΩ RAC_SNS resistor, a 6-A current limit would be achieved as: RILIM = KILIM * (2/5) / 6A = 3.3 kΩ.