IRU3033

6

Rev. 1.7

07/17/02

www.irf.com

Mode of Operation

Switching

Linear

TYPICAL APPLICATION

5V to 3.3V for Pentium Application with AGP or Pentium II Application without ATX power supply Dual

mode Operation between Switching or Linear mode.

Figure 4 - This unique application of IRU3033 allows the designer to switch between Linear or Switching mode of

operation using a single IC. This circuit has the flexibility to be used for low current operation in Linear mode for cost

reasons and yet be able to operate in the Switching mode if the load current increases and the heat generated by

the Linear operation will be an issue.

The table below describes the components that will be effected for the two modes of operation.

L1

V

S

L2

V

S

V = See parts list for value

S = Short

O = Open

D1

V

O

C4

V

O

C5

V

O

R1A

O

V

R1B

V

O

R2

V

O

R3

V

O

R4

V

V

R5

V

O

R6

V

V

R7

O

V

5V

C1

L1

C3

Q2

C2

L2

R4

C7

R6

R7

D1

R2

C4

R5

R1A

R1B

12V

R3

C5

C8

R9

R10

R13

C9

Drv1

Gnd

Drv2

U1