CYT 6167
PD(MAX) = (TJ(MAX)- TA)/θJA. Exceeding the maximum allowable power dissipation will result
in excessive die temperature, and the regulator will go into thermal shutdown. See Table 1 and
the “Thermal Considerations” section for details.
Note 4: Output voltage temperature coefficient is the worst-case voltage change divided by the total
temperature range.
Note 5: Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts
are tested for load regulation in the load range from 100µA to 400mA. Changes in output voltage
due to heating effects are covered by the thermal regulation specification.
Note 6: Dropout voltage is defined as the input to output differential at which the output voltage drops 2%
below its nominal value measured at 1V differential.
Application Hints
Like any Low dropout regulator, CYT6167 requires external capacitors to ensure stability. The
external capacitors must be carefully selected to ensure the performances.
Input Capacitor:
An Input Capacitor of at least 2.2uF is required. Ceramic or Tantalum can be used. The value can
be increased without upper limit.
Output Capacitor:
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 2.2uF but
once again its value can be increased without limit.
Thermal Consideration
It is important that the thermal limit of the package should not be exceeded. The CYT6167 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:
The Power Dissipation (PD) is
PD = IOUT * [VIN – VOUT]
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 250°C/W for CYT6167. CYT6167 is
designed to enter thermal protection at 150°C. For example, if TA is 25°C then the max PD is limited to
about 0.5W. In other words, if IOUT(MAX) = 400mA, then [VIN – VOUT] can not exceed 1.25V.
ShenZhen CYT IC Design CO ,Ltd
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