ADP2389/ADP2390

Data Sheet

the ESR of the output capacitor must be less than 3.78 mΩ. It is

recommended that five 100 µF, X5R, 6.3 V ceramic capacitors

be used, such as the GRM32ER60J107ME20 from Murata, with

an ESR of 2 mΩ.

COMPENSATION COMPONENTS

For better load transient and stability performance, set the cross

The 100 µF ceramic output capacitors have a derated value of

62 µF.

Ω

=

×

×

×

×

×

×

×

=

k

47

.

19

A/V

20

μS

500

V

6

.

0

kHz

50

μF

62

5

V

2

.

1

C

R

(

)

pF

1623

k

47

.

19

μF

62

5

002

.

0

1

.

0

=

Ω

×

×

Ω

+

Ω

=

C

C

pF

8

.

31

k

47

.

19

μF

62

5

002

.

0

=

Ω

×

×

Ω

=

CP

C

SOFT START TIME PROGRAM

The soft start feature ramps up the output voltage in a controlled

manner, eliminating output voltage overshoot during soft start,

and limiting the inrush current. Set the soft start time to 4 ms.

4 ms 3.4 μA 22.67 nF

0.6 V

0.6 V

SS

SS

SS

tI

C

××

=

=

=

INPUT CAPACITOR SELECTION

Place a minimum 10 µF ceramic capacitor near the PVIN pin.

In this application, one 10 µF, X5R, 25 V ceramic capacitor is

recommended.

SCHEMATIC FOR DESIGN EXAMPLE

Figure 32. Schematic for Design Example

BST

FB

COMP

PGOOD

GND

VREG

RT

ILIM

FTW

SS

L

0.68µH

1µF

121kΩ

SW

PGND

EN

PVIN

VIN

10µF

25V

0.1µF

100µF

6.3V

100µF

6.3V

100µF

6.3V

100µF

6.3V

100µF

6.3V

10kΩ

10kΩ

1500pF

20kΩ

22nF

33pF

ADP2389/

ADP2390

Rev. 0 | Page 18 of 23