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BS67F340/BS67F350/BS67F360/BS67F370
Enhanced Touch A/D Flash MCU with LCD Driver
BS67F340/BS67F350/BS67F360/BS67F370
Enhanced Touch A/D Flash MCU with LCD Driver
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
These devices contain 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 Temperature
semsor output or Temperature sensor reference voltage, into a 12-bit digital value. The external or
internal analog signal to be converted is determined by the ACS3~ACS0 bits together with the TSE
and BGMEN bits. When the external analog signal is to be converted, the corresponding pin-shared
control bits should first be properly configured and then desired external channel input should be
selected using the ACS3~ACS0 bits.
This A/D converter also includes a temperature sensor circuitry which contains a temperature
sensor, operational amplifiers and an internal reference voltage. The temperature sensor will detect
the temperature and output a voltage proportional to the temperature. The output voltage can be
amplified by the OPA and then converted to an 12-bit digital data using the A/D converter.
The accompanying block diagram shows the internal structure of the A/D converter with temperature
sensor together with its associated registers and control bits.
Device
External Input Channels
Internal Signal
A/D Channel Select Bits
BS�7F340
BS�7F3�0
BS�7F3�0
BS�7F370
8: AN0~AN7
�: V
TSO
� V
TSVREF
ACS3~ACS0
TSE, BGMEN