SE5117
Application Hints
Thermal Consideration
Like any Low dropout regulator, SE5117 requires
external capacitors to ensure stability. The external
capacitors must be carefully selected to ensure the
performances.
It is important that the thermal limit of the package
should not be exceeded. The SE5117 has built-in
thermal protection. When the thermal limit is
exceeded, the IC will enter protection, and the VOUT
will be reset to zero. The power dissipation for a
given application can be calculated as follows:
Input Capacitor:
An Input Capacitor of at least 10uF is required.
The Power Dissipation (PD) is
Ceramic or Tantalum can be used. The value can
be increased without upper limit.
PD = IOUT * [VIN – VOUT
]
Output Capacitor:
The thermal limit of the package is then limited to
PD(MAX) = [TJ – TA]/θJA where TJ is the junction
temperature, TA is ambient temperature, and θJA is
around 135°C/W for SE5117. SE5117 is designed
An Output Capacitor is required for look stability. It
must be located no more than 1cm away from the
VOUT pin, and connected directly between VOUT and
GND pins. The minimum value is 10uF but once
again its value can be increased without limit.
to enter thermal protection at 150°C. For example, if
TA is 25°C then the max PD is limited to about 1W. In
other words, if IOUT(MAX) = 1A, then [VIN – VOUT] can
not exceed 1V.
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ESTEK [ Estek Electronics Co. Ltd ]
