Function Descriptions; Comparator Inputs And Output; Comparator Voltage Reference; Figure 32. 6-Bit Scaler For Comparator Voltage Reference Block Diagram - Holtek HT32F52342 User Manual

32-Bit Arm ® Cortex ® -M0+ MCU
HT32F52342/HT32F52352

Function Descriptions

Comparator Inputs and Output

The I/O pins used as comparator inputs or output must be configured in the AFIO controller
registers. The detail comparator I/Os information will be referred in the pin assignment table
in the datasheet. The output can also be internally connected to a variety of timer or ADC for
trigger purpose. The comparator output can be used for both internal and external functions
simultaneously.

Comparator Voltage Reference

The comparator voltage reference is a 64-tap resistor ladder network that provides a selectable
reference voltage. It also has a power-down function to conserve the power when the reference
is not used. The comparator voltage reference provides 64 distinct levels. The equation used to
calculate the comparator voltage reference is as follows:
The comparator voltage reference power source, V
V pin. The voltage source is selected by the CVRSS bit in the Comparator Control Register
REF+
CMPCR. The primary purpose of the CVREF output is to provide a reference voltage for the
analog comparator. It may also be used independently of them and configured output to CN pin
by setting the CVROE bit in the Comparator Control Register CVRCR. The settling time of the
comparator voltage reference must be considered when changing the CVREF output.

Figure 32. 6-Bit Scaler for Comparator Voltage Reference Block Diagram

Rev. 1.30
CVREF = CVRVAL × (V
CVRSS = 0
V
V
DDA
RP
V
REF+
CVRSS = 1
CVREN
6-Bit Scaler for Comparator Voltage
Reference
222 of 656
–V ) / 63,
RP SSA
, can come from either the V
RP
CVRVAL[5:0]
R
R
R
CVREF
R
R
R
R
or external
DDA
September 28, 2018