Regulator +12V or +5V input, +5V Output

Hi，Shmuel！

Because of the Rds_on of the switch, there will always be a small voltage drop (Iload*Rds_on) between Vin and Vout. So a true 5V-to-5V converter  is impossible. So, please provide the accurate value of the Vin and Vout, which you need.

BSR-MV

Shuai

Dear Shuai,

Thank you for getting back to me so quickly.

This +5V output from this regulator will be the source for further regulators down the system. We need supplies for +5V, +3.3V, +2.5V & +1.1 ! It is critical that the parts we choose are in stock or can be purchased within lets say a month. So far we have chosen the TI TPSM828223SILR  for the +5V to 2.5V, 2A - for its small total PCB area and the fact that it it is available at end of Jan 2022 from Digikey. It has an input range of +2.5 to +5.5 so for this input I am not set strictly to exactly +5V.  For the +3.3V of the same family - I could not find ANY that were available till 2023 - thus we can't use them ! Its a shame since it appears to be a "very good" solution for our needs. Is there anything you can do about this ? Do you have anything else close to this that is stocked ? What do you suggest for the +1.1V ?

The +5V supply in my design I will have to check and get bac to you exactly what my range limitation is.

Best regards

Shmuel  

My final +5V supply has  a max. range of +4.75V to +5.25V

Hi

(1) Is the range of +4.75V to +5.25V is the input voltage voltage of the IC ? If  the input voltage is lower than 5V, IC can't regulate a 5V output voltage.

(2) What is the value of the load current, when 5V to 3.3V and 5V to 1.1V.

Shuai

Dear Shuai,

(1) YES this the range of +4.75V to +5.25V is the input voltage of an IC (one of our transceivers) ?

"If  the input voltage is lower than 5V, IC can't regulate a 5V output voltage." Sorry - could you please explain this in more detail ?

(2) For both  5V to 3.3V and 5V to 1.1V supplies we are looking at a min of 2A !

Best regards

Shmuel

Hi Shmuel！

First, our team is responsible for Buck switch regulator. For a buck converter, it is a step-down DC-DC converter. The output voltage must be lower than the input voltage.

For your request: 4.75V to 5V, it is a step-up condition. 

About 5V to 3.3V, I will suggest  device to you if it is in stock or can be purchased within lets say a month.

BSR-MV

Shuai

Dear Shuai,

Sorry I was not clear ! The Transceiver on our board that requires the +5V input has a voltage range of 4.75 - 5.25 i.e. +5V +/- 0.25V.

You mentioned  an IC 5V to 3.3V what is its part No. ?

What about 5V to +1.1V ?

Best regards

Shmuel 

Hi Shmuel!

Because of the situation of out of stock in IC market, we are not sure if such an IC are in stock or out. 

For your application request: 5V to 3.3V and 5V to 1.1V. It suggests a new released IC :TPS62933. The input voltage is from 3.8V to 30V, the output current is up to 3A. Following is the link of DS.

https://www.ti.com/lit/ds/symlink/tps62933.pdf?ts=1642042945047&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fdocs%252Funiversalsearch.tsp%253FlangPref%253Den-US%2526searchTerm%253D62933%2526nr%253D15 .

For the new-released reason, the supply may be well.

Best regards

Shuai

 Dear Shuai,

Thank you for your suggestion. What about the regulator that is the source of all my supplies that needs to take either +12V or +5V INPUT and output +5V ? This +5V outputs will be the source for my other regulators but also has to supply some of my transceivers that require an input voltage range of 4.75 - 5.25 i.e. +5V +\- 0.25V.

Please provide a solution that is stocked or that can be bought within 3 months ! If the part is only available in another year there is no way for me to implement such a design.

Best regards

Shmuel