Welcome to the Battery Management Section of the TI E2E Support Community. Ask questions, share knowledge, explore ideas, and help solve problems with fellow engineers. To post a question, click on the forum tab then "New Post".
Q: What is weak battery detection of a USB input battery charger?
A:
This is an USB spec. The USB spec states that a battery can not be charged until the portable device enumerates if the battery voltage is above the "weak battery threshold". If the battery is below the weak battery threshold, the portable device is allowed to charge without enumeration for 45 minutes.The USB spec allows the designer to select the weak battery threshold for their system. The bq2415x default is 3.7V because that is a high enough voltage for most systems to power up and be able to enumerate; however, the user can program a lower value.