ADP5033 Analog Devices, ADP5033 Datasheet - Page 21

• Manufacturer Part Number: ADP5033
• Description: Dual 3 MHz, 800 mA Buck Regulators with Two 300 mA LDOs
• Manufacturer: Analog Devices

Data Sheet
The peak-to-peak output voltage ripple for the selected output
capacitor and inductor values is calculated using the following
equation:
Capacitors with lower equivalent series resistance (ESR) are
preferred to guarantee low output voltage ripple, as shown in
the following equation:
Table 9. Suggested 10 μF Capacitors
Vendor
Murata
TDK
Panasonic
V
ESR
RIPPLE
COUT
=
≤
8
×
V
I
RIPPLE
f
RIPPLE
I
SW
RIPPLE
×
C
OUT
≈
(
2
Type
X5R
X5R
X5R
π
×
f
SW
V
)
2
IN
×
L
×
C
OUT
Model
GRM188R60J106
C1608JB0J106K
ECJ1VB0J106M
Rev. A | Page 21 of 28
The effective capacitance needed for stability, which includes
temperature and dc bias effects, is a minimum of 7 μF and a
maximum of 40 μF.
The buck regulators require 10 μF output capacitors to guarantee
stability and response to rapid load variations and to transition
into and out of the PWM/PSM modes. In certain applications,
where one or both buck regulators power a processor, the
operating state is known because it is controlled by software.
In this condition, the processor can drive the MODE pin
according to the operating state; consequently, it is possible to
reduce the output capacitor from 10 μF to 4.7 μF because the
regulator does not expect a large load variation when working
in PSM mode (see Figure 47).
Case Size
0603
0603
0603
Voltage Rating (V)
6.3
6.3
6.3
ADP5033