Hi all,
I want to ask some help to correctly design a power supply circuitry with TPS799 voltage regulators.
I've this reference circuitry:
And nothing more explainations. I want to use same specifics of filters but using a TPS799. Also i want to add another TPS799 and add decoupling capacitors.
Environment where i'll use this circuit is near a 2.4ghz wifi trasmitter and some low frequencies ~75Khz noise.
Now, first of all i have some questions about TPS799:
- I see in datasheet to use 0.1uF to 1uF as input capacitor, which should i use? And what differences i may have?
- I see in datasheet to use 2.2uF or larger as output capacitor, which should i use? And what differences i may have?
This is a circuit i've designed after some advice is:
An advices i've recived is not to use FB becouse it's a poor pratice, so i've replaced it with LC filter.
I've used lowest cap size specified in datasheet. Added some random decoupling capacitors and put all togheder.
I want to ask:
- Is my circuit designed using usefull value and right component position?
- Can you check my decoupling capacitors and positions?
- Looking for original schematic image(top of the post), is this an equal design?
Some questions about electronics:
- I've placed LC filter in the output:
- Is this the same as use LC filter in input?
- Should i use the same filter in input and output?(it have a sense to filter two times the same frequency?)
- What use have FB? It may be usefull to filter wifi frequencies?
- How i can optimize values for have a good BOM(not lower, but same cap sizes for example) and have the same circuit design?
- Can i replace C7(electrolityc) cap with a ceramic?
- Should i filter with a LC filter the digital power supply?
- Is correctly wired I2C connection(i will use 4.7Kohm resistor istead of 1Kohm)?
- Should i filter in someway VCC?
- What SMD dimensions are good for this application considering that max. current is 200mA.
Thank you for any help.
