7

e.

R2 = 68.1k

Ω / [(3.30V / 0.80V) – 1] ≅ 21.5kΩ, 1%

f.

Rz2 = 68.1k

Ω (1.0V / 15V) (60khz / 15khz) ≈ 15kΩ, 1%

g.

Cz2 = 1 /

π (18kΩ) (20khz) ≈ 1,000pF, X7R

h.

Cp1 = 1 / 2

π (15kΩ) (3.6Mhz) ≈ 10pF => Select Cp1 = 22pF for noise filtering

i.

Rz3 = 2 (68.1k

Ω) (15khz) / 300khz ≈ 7.15kΩ, 1%

j.

Cz3 = 1 /

π (7.15kΩ) (300khz) ≅ 100pF, COG

k.

Cf1 = 100pF to stabilize SP7650ER internal Error Amplify

+5V INPUT WITH A TYPE III COMPENSATION APPLICATION SCHEMATIC

Figure 12 shows another example of SP7650ER configures for +5V input by simply

changing a few external resistors and capacitors components value for delivering a 0-

3A output with excellent line and load regulation.

RBST

20

CBST

6,800pF

R3

100k,1%

L1

6.8uH

C1

22uF

CVCC

2.2uF

U1

SP7650

PGND

1

PGND

2

PGND

3

GND

4

VFB

5

COMP

6

UVIN

7

GND

8

SS

9

VIN

10

VIN

11

VIN

12

VIN

13

LX

14

LX

15

LX

16

NC

17

BST

18

GND

19

GND

20

GND

21

VCC

22

LX

23

LX

24

LX

25

LX

26

DBST

CSS

47nF

CP1

22pF

3.30V

0-3A

R2

21.5k,1%

GND

C3

22uF

C3

CERAMIC

1210

X5R

5V

6.3V

VIN

SD101AWS

VOUT

GND2

RZ3

7.15k,1%

C2

0.1uF

C1

CERAMIC

0805

X5R

6.3V

CZ3

150pF

CZ2

1,000pF

R1

68.1k,1%

RZ2

15k,1%

CF1

100pF

All resistor & capacitor size

0603 unless other wise specify

fs=300Khz

Notes:

U1 Bottom-Side Layout should has

three Contacts which are

isolated from one of another, QT

& QB Drain Contact and

Controller GND Contact

Figure 12. SP7650ER Configures for Vin = 5V, Vout = 3.3V at 0-3A Output Load Current