9/14

L5973AD

4.3 ZERO LOAD

Due to the fact that the internal power is a PDMOS, no boostrap capacitor is required and so, the device works prop-

erly also with no load at the output. In this condition it works in burst mode, with random repetition rate of the burst.

4.4 APPLICATION CIRCUIT

Figure 9. Demo board Application Circuit

Table 6. Component List

Reference

Part Number

Description

Manufacturer

C1

10

µF, 25V

TOKIN

C2

POSCAP 6TPB330M

330

µF, 6.3V

Sanyo

C3

C1206C221J5GAC

220pF, 5%, 50V

KEMET

C4

C1206C223K5RAC

22nF, 10%, 50V

KEMET

R1

5.6K, 1%, 0.1W 0603

Neohm

R2

3.3K, 1%, 0.1W 0603

Neohm

R3

4.7K, 1%, 0.1W 0603

Neohm

D1

STPS2L25U

2A, 25V

ST

L1

DO3316P-153

15

µH, 3A

COILCRAFT

D03IN1454

8

4

5

1

7

L5973AD

C1

10

µF

25V

CERAMIC

C2

330

µF

6.3V

VOUT=3.3V

VIN = 4.4V to 25V

R1

5.6K

R2

3.3K

R3

4.7K

C4

22nF

C3

220pF

3

L1 15

µH

D1

STPS2L25U

COMP

VCC

OUT

FB

GND

INH

2

6

3.3V

SYNC.

VREF