The MP8860 datasheet suggests that it’s a One Time Programmable (OTP) device. Can the device be reprogrammed through I2C on-the-fly? Or just “one time?” Thanks.
Hi Stan and welcome to the forum.
The NVM (non volatile memory) is only One Time Programmable, so the settings on boot can only be set once, but the I2C interface will allow you to communicate with the device on the fly.
MP8860 I2C registers can be change on fly feasibly.
OTP ( One Time Programmable) is finished in MPS factory. It means you can customize the DEFAULT register values before we ship the samples to you.
Any question, let me know freely.
I’ll take this thread to ask something related to that.
I’m using the MP8862, which if I’m not mistaken is functionally the same as the MP8860 but with less output current capabilities, to power a variable load. This means we may have a 12V device, a 9V one, a 5V, 3.3V, etc. at the output.
The problem I have is related to the default values. If I understood the datasheet well, when driving the EN pin high, the chip enables and outputs its default Vout (which is 5V) before I could write a 0 to the EN bit of the CTL1 register through I2C. If I have a 3.3V device connected to VOUT, it could be damaged!
What can I do to prevent that?
Perhaps you could use something like the MP28167-A, since it’s OTP affects the Vref boot value. Then you could select FB Resistors to allow boot at 3.3V, which you could scale up through the I2C interface during operation?