Datasheet

Section 24 A/D Converter
REJ09B0465-0300 Rev. 3.00 Page 815 of 982
Sep 17, 2010
H8S/20103, H8S/20203, H8S/20223, H8S/20115, H8S/20215, H8S/20235 Group
Section 24 A/D Converter
This LSI includes a successive approximation type 10-bit A/D converter (one unit or two units)
that allows up to sixteen analog input channels to be selected. Figures 24.1 and 24.2 show the
block diagrams of A/D converters unit 1 and unit 2, respectively.
The differences between unit 1 and unit 2 are the number of analog input channels and the number
of data registers. The other functions of units 1 and 2 are the same.
24.1 Features
• 10-bit resolution
• Input channels
⎯ Unit 1: 12 channels for the H8S/20223, H8S/20203, H8S/20215, and H8S/20235 Groups
and 8 channels for the H8S/20103 and H8S/20115 Groups
⎯ Unit 2: 4 channels for the H8S/20223 and H8S/20235 Groups
• Conversion time: 2 µs per channel (at 20 MHz operation)
• Operating modes: Two
⎯ A/D conversion mode: A selected analog input is A/D converted
⎯ Compare mode: A selected analog input is compared with the voltage specified by the user
• Channel select modes
⎯ Single mode: Single-channel A/D conversion or comparison
⎯ Scan mode: Continuous A/D conversion on 1 to 4 channels, or 1 to 8 channels
• Data registers: 8 data registers for unit 1 and 4 data registers for unit 2
⎯ Conversion results are held in a 16-bit data register for each channel
• Sample and hold function
• Three kinds of conversion start
⎯ Conversion can be started by software, conversion start trigger by 16-bit timer (timer RC or
RD), or external trigger signal.
• Interrupt request
⎯ A/D conversion end interrupt (ADI) request can be generated
⎯ Compare result change interrupt (CMPI) request can be generated
• Module standby function can be set