PRODUCT DATASHEET
AAT2789
SystemPowerTM
Low Noise, High Frequency Dual Step-Down Converter
Printed Circuit Board Layout Recommendations
Figure 1: AAT2789 Evaluation Board
Component Side Layout.
Figure 2: AAT2789 Evaluation Board
Solder Side Layout.
U1
OUT1
L1
1
9
NC
LX1
FB1
1.5μH
C5
C2
C3
10μF
R1
VIN
opt
10μF
59K
7
11
12
VP1
VP1
VCC1
R2
59K
8
AGND1
OUT2
L2
3.3μH
C1
10μF
5
3
LX2
FB2
AAT2789
R3
C6
267K
opt
6
15
16
EN1
VP2
R4
59K
C4
10μF
4
AGND2
13
10
2
VCC2 PGND1
14
EN2
PGND2
TDFN34-16
Figure 3: AAT2789 Evaluation Board Schematic.
Symbol
Part Number
Description
Qty
U1
AAT2789
AnalogicTech 2-Output Buck TDFN34-16
1
4
1
1
1
1
1
C1, C2, C3, C4 GRM188R60J106ME47D Cap, MLC, 10uF/6.3V, 0603 ( HMAX=0.9mm), Murata
C5
C6
L1
L2
R1-R4
Generic
Generic
LQM2HPN1R5MG0
TFC252008MBT
Generic
Cap,10nF/6.3V,0402
Cap,100pF/6.3V,0402
1.5uH, ISAT=3A, 2x2.5x0.9mm (HMAX=0.95mm), shielded chip inductor, Murata
3.3uH, ISAT=0.52A, 2x2.5x1mm (HMAX=1.0mm), non-shielded chip inductor, TDK
Carbon Film resistor, 0402
Table 1: AAT2789 Bill of Materials.
w w w . a n a l o g i c t e c h . c o m
2789.2008.03.1.0
17
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
