UPD78F9418A NEC, UPD78F9418A Datasheet - Page 155

• Manufacturer Part Number: UPD78F9418A
• Description: (UPD7894xxA) 8-Bit Single Chip Microcontrollers
• Manufacturer: NEC

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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.
Voltage comparator
The voltage comparator compares an analog input with the voltage output by the series resistor string.
Series resistor string
The series resistor string is configured between AV
against which analog inputs are compared.
ANI0 to ANI6 pins
The ANI0 to ANI6 pins are analog input pins for the seven-channel A/D converter. They are used to receive
the analog signals to be subject to A/D conversion.
Caution Do not supply the ANI0 to ANI6 pins with voltages that fall outside the rated range. If a
AV
The AV
Signals received at the ANI0 to ANI6 pins are converted to digital signals based on the voltage across the
AV
AV
The AV
the V
AV
The AV
potential as the V
REF
REF
SS
DD
SS0
pin
pin
pin
and AV
REF
SS
DD
pin, even while the A/D converter is not being used.
pin is a ground potential pin for the A/D converter. This pin must be held at the same potential as
voltage greater than AV
is supplied 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.
pin is an analog power supply pin for the A/D converter. This pin must be held at the same
pin is a reference voltage pin for the A/D converter.
SS
pins.
DD0
pin, even while the A/D converter is not being used.
REF
User’s Manual U13952EJ3V0UD
or less than AV
REF
SS
and AV
(even if within the absolute maximum rating)
SS
. It generates the reference voltages
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