Switch between LDO and switched regulator

G

Gopal

Guest
Hi,
A basic design question: Can we implement some sort of "if
condition" in a circuit to choose between LDO and switched regulator.
The application is something like this.
I have a device that is ti be run at 4V to 36V range. I know thats
pretty big range. And my micro and other stuff works at 3.3V. Now, as
per power efficiency of the regulators, I know LDo is better at
voltages close to 4V and switched regulator is efficient at voltages
close to 36V. So, is there any way a circuit can be designed to choose
the LDOs deoending upon on the input voltage.

Thank you

Gopal
 
On 21 Oct 2003 13:35:58 -0700, gokeda@mailcity.com (Gopal) wrote:

Hi,
A basic design question: Can we implement some sort of "if
condition" in a circuit to choose between LDO and switched regulator.
The application is something like this.
I have a device that is ti be run at 4V to 36V range. I know thats
pretty big range. And my micro and other stuff works at 3.3V. Now, as
per power efficiency of the regulators, I know LDo is better at
voltages close to 4V and switched regulator is efficient at voltages
close to 36V. So, is there any way a circuit can be designed to choose
the LDOs deoending upon on the input voltage.

Thank you

Gopal
Click to expand...
An LDO will be about 80% efficient dropping 4 to 3.3. A good switcher
could beat this over the entire range.

John
 
Hi,
A "good switching regulator" may again take more components than
LDO. Do you have any good design schematic that can regulate 3.3V from
4V-36V .

Thanks

Gopal


John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in message news:<siobpvo9ptoa4j55fnm42078f93g2qhpun@4ax.com>...
On 21 Oct 2003 13:35:58 -0700, gokeda@mailcity.com (Gopal) wrote:

Hi,
A basic design question: Can we implement some sort of "if
condition" in a circuit to choose between LDO and switched regulator.
The application is something like this.
I have a device that is ti be run at 4V to 36V range. I know thats
pretty big range. And my micro and other stuff works at 3.3V. Now, as
per power efficiency of the regulators, I know LDo is better at
voltages close to 4V and switched regulator is efficient at voltages
close to 36V. So, is there any way a circuit can be designed to choose
the LDOs deoending upon on the input voltage.

Thank you

Gopal

An LDO will be about 80% efficient dropping 4 to 3.3. A good switcher
could beat this over the entire range.

John
Click to expand...
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top