Hi team,
We are working with this chip developing a battery charger. We are trying to undestand which is the best RAC_SNS value because page 41 from the datasheet (www.ti.com/.../bq25756.pdf says: "Input Current DPM Regulation Limit with 5mΩ" and in page 64 says: "The default input sense resistor (RAC_SNS) is 2 mΩ".
Regarding to those references, we selected a 2mΩ resistor for RAC_SNS (1000mA-50000mA with 125mA steps). With this value we detected a non common behavior of the protections.
- We selected a 10K resistor to ILIM_HIZ, to have 5A as input current regulation (But we have a hw limitation of 3.77A as input current lower than our estimated value)
- Regarding to the 2mΩ current relation we have build the following data values:
IAC_DPM Value | Measured Data
1A->0.77A
1.5A->1.17A
2A->1.57A
2.5A->1.96A
3A->2.37A
3.5A->2.76A
4A->3.15A
4.5A->3.55A
5A->3.95A
5.5A->4.36A
What have we done wrong?
