AP7362 Datasheet, PDF (9/13 Pages) Diodes Incorporated – 1.5A, LOW QUIESCENT CURRENT, FAST TRANSIENT ULTRA-LOW DROPOUT LINEAR REGULATOR

AP7362
1.5A, LOW QUIESCENT CURRENT, FAST TRANSIENT
ULTRA-LOW DROPOUT LINEAR REGULATOR
Application Information (cont.)
120
100
80 ^PHASE
60 _GAIN
40
20
0
-20 V_IN=2.7V
-40 V_OUT=1.2V
-60 _IL=0A
-80 _{COUT=10μF CER}
-100
-120
100
1k
10k
100k
140
120
100
80
60
40
20
0
-20
-40
-60
-80
1M
FREQUENCY(Hz)
Gain-Bandwidth Plot for no Load
ON/OFF Input Operation
The AP7362 is turned on by setting the EN pin high, and
is turned off by pulling it low. If this feature is not used,
the EN pin should be tied to IN pin to keep the regulator
output on at all time. To ensure proper operation, the
signal source used to drive the EN pin must be able to
swing above and below the specified turn-on/off voltage
thresholds listed in the Electrical Characteristics section
under V_IL and V_IH.
Short Circuit Protection
When output current at OUT pin is higher than current
limit threshold, the current limit protection will be triggered
and clamp the output current to prevent over-current and
to protect the regulator from damage due to overheating.
Thermal Shutdown Protection
Thermal protection disables the output when the junction
temperature rises to approximately +170°C, allowing the
device to cool down. When the junction temperature
reduces to approximately +160°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.
Low Quiescent Current
The AP7362, consumes only around 0.5mA for all input
voltage range and load currents, this provides great power
saving in portable and low power applications.
Output Noise
This is the integrated value of the output noise over a
specified frequency range. Input voltage and output load
current are kept constant during the measurement.
Results are expressed in μVrms or μV √Hz.
The AP7362 is a low noise regulator and needs no
external noise reduction capacitor. Output voltage noise is
typically 100μVrms overall noise level between 100 Hz
and 100 kHz
Noise is specified in two ways:
Output noise density is the RMS sum of all noise
sources, measured at the regulator output, at a specific
frequency (measured with a 1Hz bandwidth). This type of
noise is usually plotted on a curve as a function of
frequency.
Output noise voltage is the RMS sum of spot noise over
a specified bandwidth. Spot noise is measured in units
μV/√Hz or nV/√Hz and total output noise is measured in
μV(rms). The primary source of noise in low-dropout
regulators is the internal reference.
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 ensure 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) X I_OUT
The maximum power dissipation, handled by the device,
depends on the junction to ambient thermal resistance,
and maximum ambient temperature, which can be
calculated by the equation in the following:
P_{D _ max}
=
(+150°C - TA )
R_θJA
AP7362
Document number: DS35058 Rev. 2 - 2
9 of 13
www.diodes.com
June 2011
© Diodes Incorporated