EL7571

FN7298 Rev 1.00

Page 11 of 19

October 25, 2004

In the non-synchronous scheme a flyback diode is required to

provide a current path to the output when the high side power

forward voltage drop and condition current is a primary source

of power dissipation in the convertor. The Schottky diode

selected is the International Rectifier 32CTQ030 which has

0.4V of forward voltage drop at 15A.

Block Diagram

MANUFACTURER

MODEL

ID

VDS

PACKAGE

MegaMos

Mi4410

4.5V

20m



6.4nF

±10A

30V

SO-8

MegaMos

Mip30N03A

4.5V

22m



6.3nF

±15A

30V

TO-220

Siliconix

Si4410

4.5V

20m



4.3nF

±10A

30V

SO-8

Fuji

2SK1388

4V

37m



±17.5A

TO-220

IR

IRF3205S

4

8m



17nF (max)

±98A

55V

D2Pak

Motorola

MTB75N05HD

4

7m



7.1nF

±75A

50V

TO-220

-

+

-

+

Reference

DAC

Ramp Control

Oscillator

-

+

-

+

-

+

-

+

-

+

-

+



PWM

Control Logic

3mF

4.5V to

12.6V

1.5µH

240pF

220pF

VID

(0:4)

3.5V

4V

UVLO HI

UVLO LOW

ENABLE

0.1µF

In Regulation

Current Reversal

Soft

Start

ENABLE

5.1µH

7.5m



6mF

0.1µF

OTEN

REF

FB

PWRGD

LX

HSD

LSD

GNDP

GND