Rev. 1.00
82
August 29, 2018
Rev. 1.00
83
August 29, 2018
HT45F6530
AC Voltage Regulator Flash MCU
HT45F6530
AC Voltage Regulator Flash MCU
Over Current Protection – OCP
The device includes two over current protection functions which provide a protection mechanism
for applications. Each OCP function consists of one fully integrated Operational Amplifier and one
Comparator as well as one 12-bit R2R D/A Converter with buffer. The Operational Amplifier can be
used for signal amplification according to specific user requirements. The 12-bit D/A Converter can
provide an accurate reference voltage to the negative input of Comparator. The Comparator is used
to compare two analog voltages and provide an output based on their difference and generate an
interrupt to indicate a specific current condition has occurred if the corresponding interrupt control is
enabled.
Over Current Protection Operation
The over current protection circuit is used to prevent the input current from being in an unexpected
level range. The current on the OPAnP or OPAnN pin is converted to a voltage and then amplified
by the OCP Operational Amplifier n with adjustable bandwidth. After the current is converted and
amplified to a specific voltage level, it will be compared with a reference voltage provided by the
12-bit OCP D/A Converter n.
The OCP Operational Amplifier n and the OCP Comparator n can be configured to operate in
the normal operating mode or input offset calibration mode determined by the OnOFM bit in the
OPnVOS register and the CnOFM bit in the CMPnVOS register respectively. The OCP Operational
Amplifier n output signal can also be directly output on the OPAnO pin, or internally connected
to the A/D converter input. A buffer within the OCP D/A Converter n can enhance output driving
capability. Its reference voltage can be supplied by V
DD
or external VRnEXT pin, selected by
the DACnVRS bit in the DACnC register. The OCP Comparator n output bit, CMPnO, indicates
whether a user-defined current condition occurs or not.
If the CMPnO bit changes state from low to high, made by the specific voltages on OCP Comparator
n inputs and by the corresponding condition of the CnPOL bit, a one shot signal will be generated to
trigger an OCPn interrupt request. It is important to note that, only the rising edge of CMPnO bit can
trigger an OCPn interrupt request, so the CnPOL bit must be properly configured according to user’s
application requirements.