AnsweredAssumed Answered

LTC4155

Question asked by mchi3bt2 on Aug 9, 2018
Latest reply on Aug 9, 2018 by Zack

To whom it may concern,

 

Having issues with the amount of charge current on the LTC4155.  Summary below:

 

Setup:

- Only using WALLSNS pulled up to Vbus without overvoltage protection

- WALLGT, USBSNS, USBGT are all not connected

- CLPROG1 has 1.21k to ground

- CLPROG2 has 1.21k to ground

- PROG has 500Ohms to ground

- VBUS = 5V

- Do not have any load on VOUT

 

Issue:

- Not able to have more than 75mA of charge current when battery of 3.5V is connected.

- I2C readings show current limits is inactive and charging is Constant Current

- The 75mA is only present when writing 0xE0 to REG1.  Writing 0x1F to REG1 results in zero charge current.

 

=> Would you be able to suggest why the charge current is limited to only 75mA in this setup and why the 0xE0 must be written to enable charge current into the battery? (All other register settings are configured to default)

 

Look forward to hearing from you.

 

Many Thanks,

Bhav

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