aoz1915 Alpha & Omega Semiconductor, aoz1915 Datasheet - Page 10

• Manufacturer Part Number: aoz1915
• Description: 1.5a General Purpose Boost Regulator
• Manufacturer: Alpha & Omega Semiconductor

The power dissipation of inductor can be approximately
calculated by input current and DCR of inductor.
The actual AOZ1915 junction temperature can be
calculated with power dissipation in the AOZ1915 and
thermal impedance from junction to ambient.
The maximum junction temperature of AOZ1915 is
145°C, which limits the maximum load current capability.
The thermal performance of the AOZ1915 is strongly
affected by the PCB layout. Extra care should be taken
by users during design process to ensure that the IC will
operate under the recommended environmental
conditions.
T
P
Rev. 1.1 July 2009
junction
inductor_loss
C
=
IN
(
×
P
Θ
=
total_loss
+
I
IN
T
ambient
2
×
R
–
P
inductor
inductor_loss
C
4
FSEL
×
LX
LX
LX
SS
IN
1.1
Figure 3 . AOZ1915 PCB Layout Example
–
1
P
diode_loss
4X3 DFN-12
www.aosmd.com
AOZ1915
OUT
) ×
GND
Several layout tips are listed below for the best electric
and thermal performance.
1. Do not use thermal relief connection to the V
2. A ground plane is preferred.
3. Make the current trace from LX pins to L to Co to the
4. Pour copper plane on all unused board area and
5. Keep sensitive signal trace such as trace connected
6. The output schottky diode is integrated into
the GND pin. Pour a maximized copper area to the
GND pin and the V
GND as short as possible.
connect it to stable DC nodes, like V
V
with FB pin and COMP pin far away from the LX pin.
AOZ1915. Proper layout should incorporate thermal
via connection from top to bottom layers.
OUT
.
12
OUT
GND
GND
EN
FB
COMP
IN
R
C
3
pin to help thermal dissipation.
OUT
R
2
C
3
R
1
IN
, GND or
AOZ1915
Page 10 of 14
IN
and