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Rev. 1.00
104
October 26, 2018
Rev. 1.00
105
October 26, 2018
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
Analog to Digital Converter
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements.
A/D Overview
The device contains a multi-channel analog to digital converter which can directly interface to
external analog signals, such as that from sensors or other control signals and convert these signals
directly into a 12-bit digital value. It also can convert the internal signals, such as the bandgap
reference voltage V
BG
, high voltage power VCC1 divided voltage V
CC1O
, high voltage power VCC2
divided voltage V
CC2O
and OCP operational amplifier output voltage V
OCPAO
, into a 12-bit digital
value. The external or internal analog signal to be converted is determined by the SAINS and SACS
bit fields. When the external analog signal is to be converted, the corresponding external channel
input pin function should first be properly configured and then the desired external channel input
should be selected using the SAINS and SACS fields. Note that when the internal analog signal
is selected to be converted, the SAINS and SACS fields should also be properly configured. More
detailed information about the A/D input signal selection will be described in the “A/D converter
Control Registers” and “A/D Converter Input Signals” section respectively.
External Input Channels
Internal Signals
A/D Signal Select Bits
8: AN0~AN7
4: V
BG
, V
CC1O
,
V
CC2O
, V
OCPAO
SAINS2~SAINS0,
SACS3~SACS0
The accompanying block diagram shows the internal structure of the A/D converter together with its
associated registers and control bits.
Pin-shared
Selection
SACS3~SACS0
SAINS2~SAINS0
A/D Converter
START ADBZ ADCEN
AV
SS
÷ 2
N
(N=0~7)
f
SYS
SACKS2~
SACKS0
AV
DD
AV
DD
SAVRS1~
SAVRS0
ADCEN
A/D Reference Voltage
A/D Data
Registers
ADRFS
V
BG
V
OCPAO
SADOL
SADOH
A/D Clock
V
CC1O
V
CC2O
Pin-shared
Selection
AN0
AN7
AN1
VREF
A/D Converter Structure