upd78f0114hgb-8es-a Renesas Electronics Corporation., upd78f0114hgb-8es-a Datasheet - Page 238

• Manufacturer Part Number: upd78f0114hgb-8es-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

<R>
(8) Conversion time
(9) Sampling time
11.6 Cautions for A/D Converter
(1) Operating current in standby mode
(2) Input range of ANI0 to ANI7
(3) Conflicting operations
238
This expresses the time since sampling has been started until digital output is obtained.
The sampling time is included in the conversion time in the characteristics table.
This is the time the analog switch is turned on for the analog voltage to be sampled by the sample & hold circuit.
The A/D converter stops operating in the standby mode. At this time, the operating current can be reduced by
clearing bit 7 (ADCS) and bit 0 (ADCE) of the A/D converter mode register (ADM) to 0 (see Figure 11-2).
Observe the rated range of the ANI0 to ANI7 input voltage. If a voltage of AV
(even in the range of absolute maximum ratings) is input to an analog input channel, the converted value of that
channel becomes undefined. In addition, the converted values of the other channels may also be affected.
<1> In case of conflict between A/D conversion result register (ADCR) write and ADCR read by instruction upon
<2> In case of conflict t between ADCR write and A/D converter mode register (ADM) write or analog input
the end of conversion,
ADCR read has priority. After the read operation, the new conversion result is written to ADCR.
channel specification register (ADS) write upon the end of conversion,
ADM or ADS write has priority. ADCR write is not performed, nor is the conversion end interrupt signal
(INTAD) generated.
Sampling
time
CHAPTER 11 A/D CONVERTER
User’s Manual U16961EJ4V0UD
Conversion time
REF
or higher and AV
SS
or lower