1A Positive Voltage
Regulators (Preliminary)
CYT8117
Application Hints
Thermal Considerations
Like any linear voltage regulator, CYT8117 requires
It is important that the thermal limit of the package
external capacitors to ensure stability.
The
is not exceeded. The CYT8117 has built-in
external capacitors must be carefully selected to
ensure performance.
thermal protection. When the thermal limit is
exceeded, the IC will enter protection, and VOUT
will be pulled to ground. The power dissipation
for a given application can be calculated as
following:
Input Capacitor
An input capacitor of at least 10µF is required.
Ceramic or Tantalum can be used. The value
can be increase without upper limit.
The power dissipation (PD) is
PD = IOUT * [VIN – VOUT
]
Output Capacitor
An output capacitor is required for stability. It
must be placed no more than 1 cm away from the
VOUT pin, and connected directly between VOUT
and GND pins. The minimum value is 22µF but
may be increase without limit.
The thermal limit of the package is then limited to
PD(MAX) = [TJ – TA]/ΘJA where TJ is the junction
temperature, TA is the ambient temperature, and
ΘJA is around 60°C/W for CYT8117.CYT8117 is
designed to enter thermal protection at 175°C.
For example, if TA is 25°C then the maximum PD
is limited to about 2.5W. In other words, if
IOUT(MAX) = 1A, then [VIN – VOUT] cannot exceed
2.5V.
Preliminary and all contents are subject to change without prior notice.
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