Rechargeable Battery Info for the Shoto HDK
3.7V, 900mAh capacity lithium
See article: http://help.triadsemi.com/steamvr-tracking/shoto-steamvr-hdk/what-batteries-work-with-the-shoto-hdk
See article: http://help.triadsemi.com/steamvr-tracking/shoto-steamvr-hdk/what-batteries-work-with-the-shoto-hdk
Changing battery for EVM boards?
https://steamcommunity.com/app/507090/discussions/0/135514402720064924/
Refer to the documentation from the vendor of the Fuel Gauge and Charger ICs (Texas Instruments). Specifically:
slva725 - GPC Chemical ID selection
sluu426b - bq27520evm - evaluation board for the fuel gauge
sluua35 - Tech Reference Manual for the fuel gauge
slua597 - Learning Cycle
slua449f - Going to Production
You need to perform a battery cycle while logging data during a charge and discharge cycle according to slva725 and submit the data to the GPC ChemID calculator. This will give you the ChemID of your specific battery.
Then you need to perform a learning cycle on the battery with the fuel gauge attached, according to sluu426b and slua597. This should help you generate a bq.fs file that must be programmed to the fuel gauge. Because this is a FW change at this time you would need to contact Synapse to make the change for your product. This will help you get the fuel gauge to report the correct battery capacity/charge status.
You may also want to make changes to some of the settings of the charger circuit, such as the ILIM resistor. However there are also FW settings for the charger to limit the current to avoid damaging smaller batteries such as 500mAh-1000mAh batteries. So this is another FW change you may want to implement to allow fast battery charging.
https://steamcommunity.com/app/507090/discussions/0/135514402720064924/
Refer to the documentation from the vendor of the Fuel Gauge and Charger ICs (Texas Instruments). Specifically:
slva725 - GPC Chemical ID selection
sluu426b - bq27520evm - evaluation board for the fuel gauge
sluua35 - Tech Reference Manual for the fuel gauge
slua597 - Learning Cycle
slua449f - Going to Production
You need to perform a battery cycle while logging data during a charge and discharge cycle according to slva725 and submit the data to the GPC ChemID calculator. This will give you the ChemID of your specific battery.
Then you need to perform a learning cycle on the battery with the fuel gauge attached, according to sluu426b and slua597. This should help you generate a bq.fs file that must be programmed to the fuel gauge. Because this is a FW change at this time you would need to contact Synapse to make the change for your product. This will help you get the fuel gauge to report the correct battery capacity/charge status.
You may also want to make changes to some of the settings of the charger circuit, such as the ILIM resistor. However there are also FW settings for the charger to limit the current to avoid damaging smaller batteries such as 500mAh-1000mAh batteries. So this is another FW change you may want to implement to allow fast battery charging.