Chapter 19 8/10-Bit A/D Converter; Overview Of 8/10-Bit A/D Converter - Fujitsu F2MC-16LX Hardware Manual

CHAPTER 19 8/10-BIT A/D CONVERTER

19.1

Overview of 8/10-bit A/D Converter

The 8/10-bit A/D converter has a function to convert the analog input voltage to the 8-bit
or 10-bit digital value by the RC sequential comparison conversion method. The input
signal can be selected from the 16-channel analog input terminal. The conversion start
can be selected from three types of the software, the PPG timer 1 output, and the trigger
input start from external terminal.
Function of 8/10-bit A/D Converter
There is a function having following features to perform the A/D conversion of the analog voltage input
from the analog input terminal (input voltage) to the digital value:
• The conversion time is a minimum of 7.16 µs (including the sampling time using the 24 MHz machine
clock).
• Sampling time is 3.33 µs or more (machine clock 6 MHz time).
• The used conversion method is the RC sequential compare conversion method with sample hold circuit.
• The analog input terminal can be selected from the 16 channels using the program.
• The interrupt request can be generated at the A/D conversion termination and the EI
started.
No data are lost in the interrupt enable status since the conversion data protection function works even
in the continuous conversion.
• The conversion start factor can be selected from the software, the PPG timer 1 output (rising edge), and
the external trigger input (falling edge).
Conversion mode has three types shown in Table 19.1-1.
Table 19.1-1 Conversion Modes of 8/10-bit A/D Converter
Conversion Single conversion operation
Mode
Single-shot The specified channel (one channel
conversion only) is converted for one time and
mode terminated.
Continuous
The specified channel (one channel
conversion
only) is repetitively converted.
mode
Pause- The specified channel (one channel
conversion only) is converted for one time and
mode suspended until the next start.
430
Scanning conversion operation
Continuous plural channels (maximum 16 channels can be
specified) are converted for one time and terminated.
Continuous plural channels (maximum 16 channels can be
specified) are repetitively converted.
Continuous plural channels (maximum 16 channels can be
specified) are converted.
However, one channel is converted and suspended until the next
start.
2
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