UPD78F0034BGC-8BS-A Renesas Electronics America, UPD78F0034BGC-8BS-A Datasheet - Page 271

• Manufacturer Part Number: UPD78F0034BGC-8BS-A
• Description: MCU 8-Bit 78K0 CISC 32KB Flash 2.5V/3.3V/5V 64-Pin LQFP
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0034BGC-8BS-A

• Package: 64LQFP
• Family Name: 78K0
• Maximum Speed: 12 MHz
• Ram Size: 1 KB
• Program Memory Size: 32 KB
• Operating Supply Voltage: 2.5|3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 51
• Interface Type: 3-Wire/UART
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

13.5 How to Read A/D Converter Characteristics Table
(1) Resolution
(2) Overall error
(3) Quantization error
Here we will explain the special terms unique to A/D converters.
This is the minimum analog input voltage that can be identified. That is, the percentage of the analog input voltage
per 1 bit of digital output is called 1LSB (Least Significant Bit). The percentage of 1LSB with respect to the full
scale is expressed by %FSR (Full Scale Range).
When the resolution is 8 bits,
1LSB = 1/2
Accuracy has no relation to resolution, but is determined by overall error.
This shows the maximum error value between the actual measured value and the theoretical value.
Zero scale error, full scale error, integral linearity error, differential linearity error and errors which are
combinations of these express overall error.
Furthermore, quantization error is not included in overall error in the characteristics table.
When analog values are converted to digital values, there naturally occurs a 1/2LSB error. In an A/D converter,
an analog input voltage in a range of 1/2LSB are converted to the same digital code, so a quantization error
cannot be avoided.
Furthermore, it is not included in the overall error, zero scale error, full scale error, integral linearity error, and
differential linearity error in the characteristics table.
1 …… 1
0 …… 0
= 0.4%FSR
0
Figure 13-8. Overall Error
8
Ideal line
= 1/256
CHAPTER 13 8-BIT A/D CONVERTER ( PD780024A, 780024AY SUBSERIES)
Analog input
Overall
error
AV
REF
User’s Manual U14046EJ5V0UD
1 …… 1
0 …… 0
Figure 13-9. Quantization Error
0
1/2LSB
Analog input
1/2LSB
Quantization error
AV
REF
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