Other Parts Discussed in Thread: LP2985,
Hello,
i use a LP2985 which regulates 5V to 3,3V.
Cin is 4,7u and Cou 10u, both ceramic.
The problem is, that my MSP430FR5739 does not power up the first time i connect to supply voltage.
If i disconnect and connect again within 10 seconds, the uC powers up.
uC is set to 24MHz.
If i disconnect wait several minutes, and then connect, again, it won't power up.
Interestingly, it works fine, if i use another 12V supply source.
The uC has just a 10k resistor at the reset pin, without cap. It works with 12V, but not with 5V.
So i changed the regulator caps 1uF,4,7u,10u, all combinations.
Didn't work.
Then i tried to Change the RESET pin resistor and add an cap.
Picked diefferent combinations 10k, 150k,1m with 1u,4,7u,10u,100u.
Nothing worked.
Then i changed the Regulator to another, i don't know which one, still didnt work.
So i dont know what to do further.
