CHAPTER 11 10-BIT A/D CONVERTER (µPD789436 AND 789456 SUBSERIES)
(3) Sample & hold circuit
The sample & hold circuit samples consecutive analog inputs from the input circuit, one by one, and sends
them to the voltage comparator. The sampled analog input voltage is held during A/D conversion.
(4) Voltage comparator
The voltage comparator compares an analog input with the voltage output by the series resistor string.
(5) Series resistor string
The series resistor string is configured between AVDD and AVSS. It generates the reference voltages
against which analog inputs are compared.
(6) ANI0 to ANI5
Pins ANI0 to ANI5 are the 6-channel analog input pins for the A/D converter. They are used to receive the
analog signals for A/D conversion.
Caution Do not supply pins ANI0 to ANI5 with voltages that fall outside the rated range. If a voltage
greater than AVDD or less than AVSS (even if within the absolute maximum rating) is applied
to any of these pins, the conversion value for the corresponding channel will be undefined.
Furthermore, the conversion values for the other channels may also be affected.
(7) AVSS pin
The AVSS pin is a ground potential pin for the A/D converter. This pin must be held at the same potential as
the VSS pin, even while the A/D converter is not being used.
(8) AVDD pin
The AVDD pin is an analog power supply pin for the A/D converter. This pin must be held at the same
potential as the VDD pin, even while the A/D converter is not being used.
User’s Manual U15075EJ1V0UM00
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NEC [ NEC ]
