UPD78F0413GA-GAM-AX NEC, UPD78F0413GA-GAM-AX Datasheet - Page 292

• Manufacturer Part Number: UPD78F0413GA-GAM-AX
• Description: 8BIT UC, 32K FLASH, 1KB RAM, LCD
• Manufacturer: NEC

Specifications of UPD78F0413GA-GAM-AX

• Controller Family/series: UPD78F
• No. Of I/o's: 30
• Ram Memory Size: 1024Byte
• Cpu Speed: 10MHz
• No. Of Timers: 8
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 32KB
• Oscillator Type: External, Internal

12.2 Configuration of 10-Bit Successive Approximation Type A/D Converter
(1) ANI0 to ANI5 pins
(2) Sample & hold circuit
(3) Series resistor string
(4) Voltage comparator
(5) Successive approximation register (SAR)
(6) 10-bit A/D conversion result register (ADCR)
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The 10-bit successive approximation type A/D converter includes the following hardware.
These are the 6-channel analog input pins of the 10-bit successive approximation type A/D converter. They input
analog signals to be converted into digital signals. Pins other than the one selected as the analog input pin can
be used as I/O port pins or segment output pins.
The sample & hold circuit samples the input voltage of the analog input pin selected by the selector when A/D
conversion is started, and holds the sampled voltage value during A/D conversion.
The series resistor string is connected between AV
the sampled voltage value.
The voltage comparator compares the sampled voltage value and the output voltage of the series resistor string.
This register converts the result of comparison by the voltage comparator, starting from the most significant bit
(MSB).
When the voltage value is converted into a digital value down to the least significant bit (LSB) (end of A/D
conversion), the contents of the SAR register are transferred to the A/D conversion result register (ADCR).
The A/D conversion result is loaded from the successive approximation register to this register each time A/D
conversion is completed, and the ADCR register holds the A/D conversion result in its higher 10 bits (the lower 6
bits are fixed to 0).
CHAPTER 12 10-BIT SUCCESSIVE APPROXIMATION TYPE A/D CONVERTER ( PD78F041x only)
Figure 12-2. Circuit Configuration of Series Resistor String
AV
AV
REF
SS
User’s Manual U18698EJ1V0UD
P-ch
Series resistor string
REF
and AV
SS
, and generates a voltage to be compared with
ADCS