400mA Super LDO Linear
Regulator
CYT6119
Application Hints
Thermal Consideration
Like any Low dropout regulator,CYT6119 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 CYT6119 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.
Ceramic or Tantalum can be used. The value can
be increased without upper limit.
The Power Dissipation (PD) is
PD = IOUT * [VIN – VOUT
]
The thermal limit of the package is then limited to
D(MAX) = [TJ – TA]/θJA where TJ is the junction
Output Capacitor:
An Output Capacitor is required for look stability. It
must be located no more than 1cm away from the
P
temperature, TA is ambient temperature, and θJA is
around 180°C/W for CYT6119. CYT6119 is designed
to enter thermal protection at 150°C. For example, if
TA is 25°C then the max PD is limited to about 0.7W.
In other words, if IOUT(MAX) = 400mA, then [VIN –
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.
VOUT] can not exceed 1.75V.
All contents are subject to change without prior notice.
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