AT90PWM2B-16SE ATMEL [ATMEL Corporation], AT90PWM2B-16SE Datasheet - Page 245

• Manufacturer Part Number: AT90PWM2B-16SE
• Description: 8-bit Microcontroller with 8K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

4317J–AVR–08/10
Figure 21-14. Differential Measurement Range
Table 21-2.
Example 1:
V
V
V
...
V
V
V
...
V
V
V
ADCn
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
–
–
–
+ 0.999 V
+ 0.998 V
+ 0.001 V
- 0.001 V
- 0.999 V
- V
+ V
ADMUX = 0xED (ADC3 - ADC2, 10x gain, 2.56V reference, left adjusted result)
Voltage on ADC3 is 300 mV, voltage on ADC2 is 500 mV.
ADCR = 512 * 10 * (300 - 500) / 2560 = -400 = 0x270
- V
REF
REF
REF
/Gain
/GAIN
/GAIN
Correlation Between Input Voltage and Output Codes
REF
REF
REF
REF
REF
/GAIN
/GAIN
/GAIN
/GAIN
/GAIN
Read code
0x1FF
0x1FF
0x1FE
0x3FF
Output Code
0x001
0x000
0x201
0x200
0x3FF
...
...
0x1FF
0x000
0x200
0
Corresponding decimal value
511
511
510
...
1
0
-1
...
-511
-512
AT90PWM2/3/2B/3B
V
REF
/Gain
Differential Input
Voltage (Volts)
245