LDO Fast ttransient response

[pelo]

Hi,

i would like to know how can i improve the transient response of my LDO

I use a Nmos as Pass device and my system is well compensated but i want to have a bettre transient response.

My LDO is an on chip LDO (capacitor less LDO = internal capacitor)

VDD = 3v

Ilaod max = 30mA

Anybody can help me please?????

 

[Vamsi Mocherla]

Try and send in the circuit/block diagram.

 

[eezou]

What structure is your ldo? Can you give your simulation results?

 

[smartdream]

Hi,

i would like to know how can i improve the transient response of my LDO

I use a Nmos as Pass device and my system is well compensated but i want to have a bettre transient response.

My LDO is an on chip LDO (capacitor less LDO = internal capacitor)

VDD = 3v

Ilaod max = 30mA

Anybody can help me please?????

You should increase the GBW of close loop.
you can increse the rail current of OPAMP or use class AB for outpout stage.
good luck.

 

[jefferson]

Notice the W/L of the NMOS pass device,your Imax is not very big,so the pass device needn't a big W/L rate.

 

[melodyseu]

Try some Slew rate enhancement circuit to improve the OPA's slew rate performance

 

[ballballball]

Hi,
How to get a good stability without Cout??

 

[jcpu]

Transient behavior has to modeled wit load.
A closed loop control system can be predicted by matlab...

To improve, parameters has to be specific.
as well as the transient test condition...is it load change
or is it VDD change? how much?

all upstairs are possible, but shall affect other performance.

Have fun,

 

[hackjiang]

Remove in-band doublet is more helpful.
Find them carefully.
Regards.