Datasheet

TPS53313
VIN SW
V
IN
Output All MLCCs
UDG-11254
C
BST
PG
FB
COMP
BP7
AGND
RT/SYNC
EN
MODE/SS
VBST
PowerPad
PGND
BP3
V
IN
V
OUT
EN
PGOOD
( )
IN OUT OUT
L(ripple)
SW IN
V V V
1
I
L f V
- ´
= ´
´
RIPPLE RIPPLE(C) RIPPLE(ESR) RIPPLE(ESL)
V V V V= + +
TPS53313
www.ti.com SLUSAS8 –DECEMBER 2011
APPLICATION INFORMATION
DESIGN EXAMPLE
The following example illustrates the design process and component selection for a single-output synchronous
buck converter using the TPS53313. The design example schematic of a is shown in Figure 13. The specification
of the converter is listed in Table 3.
Table 3. Design Example Converter Specifications
PARAMETER TEST CONDITION MIN TYP MAX UNIT
V
IN
Input voltage 10.8 12.0 13.2 V
V
OUT
Output voltage 1.2 V
V
RIPPLE
Output ripple I
OUT
= 6 A 1% of V
OUT
V
I
OUT
Output current 6 A
f
SW
Switching frequency 600 kHz
Figure 13. Typical 12-V input Application Circuit Diagram
Output Inductor Selection
The inductance value should be determined to give the ripple current of approximately 20% to 40% of maximum
output current. The inductor ripple current is determined by
(1)
The inductor also requires a low DCR to achieve good efficiency, as well as enough room above peak inductor
current before saturation.
Output Capacitor Selection
The output capacitor selection is determined by output ripple and transient requirement. When operating in CCM,
the output ripple has three components:
(2)
Copyright © 2011, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Link(s) :TPS53313