LM3485 12V/10A

[Ajay]

Hi,
I am using an LM3485 to design a power conditioning cicuit that can
drive 10A at 12V (i/p 12 to 30V) . I am facing this interesting issue
-
As I need to have higher current the device size (of the PFET)
increases which in turn increases the input capacitance. However the
LM3485 can drive PFETs with less that 1000pF input capacitance. It is
very difficult to get a PFET with lower i/p capacitance

This does not turn on the transistor properly. Has anybody dealt with
this situation and is there a solution to this.

Lemme know

Ajay

 

[Dieter Wiedmann]

Hi,
I am using an LM3485 to design a power conditioning cicuit that can
drive 10A at 12V (i/p 12 to 30V) . I am facing this interesting issue
-
As I need to have higher current the device size (of the PFET)
increases which in turn increases the input capacitance. However the
LM3485 can drive PFETs with less that 1000pF input capacitance. It is
very difficult to get a PFET with lower i/p capacitance

This does not turn on the transistor properly. Has anybody dealt with
this situation and is there a solution to this.

Use a complementary emitter follower to drive the MOSFET.


Regards,
Dieter