Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Maximum LDO output current?

Status
Not open for further replies.

ilikebbs

Advanced Member level 4
Joined
Nov 30, 2002
Messages
105
Helped
3
Reputation
6
Reaction score
1
Trophy points
1,298
Activity points
718
some IC claims that LDO controller is integrated. One output pin is used to control external MOSFET to generate low voltage. so what is the main factor to determine the maximum output current of LDO? Thanks.

ilikebbs
 

rhaynes

Member level 5
Joined
Feb 8, 2011
Messages
84
Helped
37
Reputation
74
Reaction score
37
Trophy points
1,298
Location
Oceanside, CA, USA
Activity points
1,996
That external MOSFET is used as the final pass element. So the final current will depend on the current rating (size) of the MOSFET but there are limits to the choices of the MOSFET. The loop stability is affected by the MOSFET gate capacitance and gain. The manufacturer probably has some recommendations for the parts and you need to stay near them in terms of gate capacitance and gain which is very closely related to the max current rating of the MOSFET.

Ray
 
Last edited:

nxtech

Full Member level 5
Joined
Jun 13, 2007
Messages
258
Helped
17
Reputation
34
Reaction score
2
Trophy points
1,298
Location
NO HIDDEN LINKS
Activity points
2,772
The final determining factor current capability for a LDO is the pass element whether its a BJT or MOSFET.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top