Hello everybody!
I'm new to the forum so let me start greeting everybody.
I'm a young electronic engineer and starting to build experience in circuit designing and developemnt on my own, since where I work I'm "the expert"... the only electronic guy...
Ow well, I see along lonly road ahead...
Now the question: voltage regulator stability.
I used quite some times before the classicla LM78XX devices, always with no issue. Now I have to develop a circuit that takes a not-so-stable 12V input (could be as high a 19 in spikes) and bring it down to 5V. I started with the LVT1117-05 and after some time of the circuit being on, I hear acoustic noise...
From there I start to dig.. and the ceramic capacitor can have that issue... ok, got it now... but now the other questions arrived...
A lot of regulator, mostly LDO seems to not be declared stable from the datasheets using them, the ESR is too low. I was planning on using LM340-0.5 but on that datasheet I was not able to find any reference on capacitor caramic or not.
I don't feel safe in using tantalium becaus of the possibility of the high spikes.
Can anybody shed some light on this topic? well, both on the specific device LM340 and if possible in general on the stability/instability issues and design good practice for supply solutions?
Thank you a lot in advance!
Best regards
I'm new to the forum so let me start greeting everybody.
I'm a young electronic engineer and starting to build experience in circuit designing and developemnt on my own, since where I work I'm "the expert"... the only electronic guy...
Ow well, I see along lonly road ahead...
Now the question: voltage regulator stability.
I used quite some times before the classicla LM78XX devices, always with no issue. Now I have to develop a circuit that takes a not-so-stable 12V input (could be as high a 19 in spikes) and bring it down to 5V. I started with the LVT1117-05 and after some time of the circuit being on, I hear acoustic noise...
From there I start to dig.. and the ceramic capacitor can have that issue... ok, got it now... but now the other questions arrived...
A lot of regulator, mostly LDO seems to not be declared stable from the datasheets using them, the ESR is too low. I was planning on using LM340-0.5 but on that datasheet I was not able to find any reference on capacitor caramic or not.
I don't feel safe in using tantalium becaus of the possibility of the high spikes.
Can anybody shed some light on this topic? well, both on the specific device LM340 and if possible in general on the stability/instability issues and design good practice for supply solutions?
Thank you a lot in advance!
Best regards