Tool/software:
Hi Team,
I have one question regarding REG1 control, my customer has enabled REG1 through OTP once, is it doable to disable REG1(back to the default state) through OTP afterwards?
Regards,
Charles
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Tool/software:
Hi Team,
I have one question regarding REG1 control, my customer has enabled REG1 through OTP once, is it doable to disable REG1(back to the default state) through OTP afterwards?
Regards,
Charles
Hello Charles,
Yes, it is possible through OTP afterwards. Please remember that there is a limit to how many times you can make partial changes with OTP. That section of the BQ769x2 Calibration and OTP Programming Guide should be useful for steps.
Best Regards,
Alexis
Hi Alexis,
Thanks for your reply.
BTW, if the OTP programming times is exceeded, is there any hardware workaround(by external circuitry) to turn off REG1?
Regards,
Charles
Hello Charles,
There isn't really a hardware workaround through external circuitry to turn off REG1 without sending a command.
Best Regards,
Alexis
Hi Alexis,
Thanks for your reply, one more question here, what about reprogramming OTP for other parameters like 0x933B Cell Balance Min Cell V (Charge)?
For example, could user set cell balancing min cell voltage to 3600mV for first OTP, and set 500mV for second OTP? Or will BQ76952 XOR these two values?
Regards,
Charles
Hello Charles,
Yes, at power-up, ‘the device will XOR each setting in the first OTP image with the corresponding setting in the second OTP image' to allow the device to load the programmed OTP values.
Section 3.2 Configuration Using OTP or Registers in the technical reference manual explains this further.
Best Regards,
Alexis
Hi Alexis,
One question here, my customer wants to set 1st OTP image to 3600mV(Cell Balance Min Cell V), and 2nd OTP to 8080mV to get the result of 4480mV.
However, 8080mV is out of Cell Balance Min Cell V range(ranging from 0mV to 5000mV), is it doable?
Regards,
Charles
Hello Charles,
I apologize for the confusion from my previous statement. The XOR at power up is to load the programmed OTP values. The way that the OTP is saved necessitates this method but allows for programming the OTP multiple times. I have corrected that statement.
This does NOT average the settings between the two OTP images.
You do NOT need to program 8080mV to get the result of 4480mV.
If the device is programmed with 3600mV and then reprogrammed with 8080mV (which is out of range and cannot be done anyway), the setting would be 8080mV going forward, not 8080-3600.
Best Regards,
Alexis
Hi Alexis,
I still feel a bit confused.
According to BQ76952 FAQ, if second OTP is used, it seems the final result will be the XOR of first & second frames...
Pls correct me if I miss understand anything here, thanks.
Regards,
Charles
Hello Charles,
The XOR that the FAQ and the TRM both refer to, just describes how the device loads up the programmed OTP values. This BQ76952 OTP FAQ answers what are they key things to be aware for OTP programming with our device.
As mentioned previously: If the device is programmed with 3600mV and then reprogrammed with 8080mV (which is out of range and cannot be done anyway), the setting would be 8080mV going forward, not 8080-3600. If the user would like to first program with 3600mV and set 5000mV for second OTP, the device will NOT XOR the values. The setting would be 5000mV going forward.
Best Regards,
Alexis