AP7167_10 Datasheet, PDF (10/14 Pages) Diodes Incorporated – 1.2A LOW DROPOUT REGULATOR WITH POK

AP7167
1.2A LOW DROPOUT REGULATOR WITH POK
Application Notes (Continued)
Low Quiescent Current
The AP7167, consuming only around 150µA for all input
range and output loading, provides great power saving in
portable and low power applications.
Wide Output Range
The AP7167, with a wide output range of 0.8V to 5.0V,
provides a versatile solution for many portable and low
power applications.
Thermal Shutdown Protection
Thermal protection disables the output when the junction
temperature rises to approximately +155°C, allowing the
device to cool down. When the junction temperature
reduces to approximately +130°C the output circuitry is
enabled again. Depending on power dissipation, thermal
resistance, and ambient temperature, the thermal
protection circuit may cycle on and off. This cycling limits
the heat dissipation of the regulator, protecting it from
damage due to overheating.
Power Dissipation
The device power dissipation and proper sizing of the
thermal plane that is connected to the thermal pad is
critical to avoid thermal shutdown and ensuring reliable
operation. Power dissipation of the device depends on
input voltage and load conditions and can be calculated
by:
P_D = (V_IN − V_OUT )xI_OUT
The AP7167 is available in the DFN3030-10 and SOP-8L-
EP packages, both with exposed pad, which is the primary
conduction path for heat to the printed circuit board (PCB).
The pad can be connected to ground or be left floating;
however, to ensure the device will not overheat, it should
be attached to an appropriate amount of copper PCB area.
However, the maximum power dissipation that can be
handled by the device depends on the maximum junction
to ambient thermal resistance, maximum ambient
temperature, and maximum device junction temperature,
which can be approximated by the equation below:
P_D (max@ T_A
)
=
(+150°C −
R _θJA
T_A
)
AP7167
Document number: DS31252 Rev. 7 - 2
10 of 14
www.diodes.com
September 2010
© Diodes Incorporated