US3036

4-5

Rev. 1.1

12/4/98

Figure 2- The circuit in figure 2 is the application of the US3036 providing a low cost solution for a 2.5V supply from

the 5V dual supply.

TYPICAL APPLICATION

TYPICAL APPLICATION

5V to 2.5V for RDRAM Supply

3036app2-1.0

Vout

C1

L1

C3

Q2

C2

L2

R4

C7

D1

R2

C4

R5

R1

R3

C5

C8

US3036

R6

C6

R7

1

2

3

4

5

6

7

8

Drv Vcc

Vfb

NC

Gnd

CS-

CS+

SS

ATX

P.S.

5V

5V(S.B.)

Ref Desig

Description

Qty

Part #

Manufacturer

U1

LDO/Switcher IC

1

US3036CS ( 8 pin SOIC)

Unisem

Q2

MOSFET

1

IRF7204 (8 pin SOIC) or IRF7406 for 4A

IR

P Ch

SI9435DY (8 pin SOIC) or SI4431 for 4A

Temic

D1

Schottky Diode

1

SK33DICT (SMC)

Lite on

L2

Inductor

1

Core:T44-52,L=6 uH

Micro Metal

Turns: 15T, 20 AWG

(core)

L1

Inductor

1

L=1 uH

R1

Resistor

1

10 ohm,5%, SMT 1206 size

R2

Resistor

1

10 ohm, 5%, SMT 1206 size

R3

Resistor

1

200 kohm,1%, SMT 0805 size

R4

Resistor

1

1 kohm,1%, SMT 0805 size

R5

Resistor

1

1 kohm,1%, SMT 0805 size

R6

Resistor

1

1 kohm,5%

R7

Resistor

1

3.57 kohm,1%, SMT 0805 size

C1

Capacitor

1

470uF,10V, Elect

Sanyo

C2

Capacitor

1

10CV1000DX, 1000uF,10V, Elect ,ESR=0.07 Ohm

Sanyo

C3

Capacitor

1

1 uF,Ceramic, SMT 0805 size

C4

Capacitor

1

470 pF,Ceramic, SMT 0805 size

Sanyo

C5

Capacitor

1

10 pF,Ceramic, SMT 0805 size

Sanyo

C6

Capacitor

1

0.1uF

C7

Capacitor

1

10CV1000DX, 1000uF,10V, Elect ,ESR=0.07 Ohm

Sanyo

C8

Capacitor

1

0.15 uF