AT90PWM216-16SUR Atmel, AT90PWM216-16SUR Datasheet - Page 248

• Manufacturer Part Number: AT90PWM216-16SUR
• Description: MCU AVR 16K FLASH 16MHZ 24SOIC
• Manufacturer: Atmel
• Series: AVR® 90PWM Lightingr

Specifications of AT90PWM216-16SUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 19
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 24-SOIC (7.5mm Width)
• Processor Series: AT90PWMx
• Core: AVR8
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRFBKIT, ATAVRISP2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

21.8
21.8.1
248
ADC Register Description
AT90PWM216/316
ADC Multiplexer Register – ADMUX
Table 21-2.
Example 1:
Example 2:
The ADC of the AT90PWM216/316 is controlled through 3 different registers. The ADCSRA and
The ADCSRB registers which are the ADC Control and Status registers, and the ADMUX which
allows to select the Vref source and the channel to be converted.
The conversion result is stored on ADCH and ADCL register which contain respectively the most
significant bits and the less significant bits.
Bit
Read/Write
Initial Value
• Bit 7, 6 – REFS1, 0: ADC Vref Selection Bits
V
V
V
...
V
V
V
...
V
V
V
ADCn
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
ADCm
– 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
– ADCL will thus read 0x00, and ADCH will read 0x9C.
– ADMUX = 0xFB (ADC3 - ADC2, 1x gain, 2.56V reference, left adjusted result)
– Voltage on ADC3 is 300 mV, voltage on ADC2 is 500 mV.
– ADCR = 512 * 1 * (300 - 500) / 2560 = -41 = 0x029.
– ADCL will thus read 0x40, and ADCH will read 0x0A.
+ 0.999 V
+ 0.998 V
+ 0.001 V
- 0.001 V
- 0.999 V
- V
Writing zero to ADLAR right adjusts the result: ADCL = 0x70, ADCH = 0x02.
Writing zero to ADLAR right adjusts the result: ADCL = 0x00, ADCH = 0x29.
+ V
REF
REF
/GAIN
/GAIN
Correlation Between Input Voltage and Output Codes
REF
REF
REFS1
REF
REF
REF
R/W
7
0
/GAIN
/GAIN
/GAIN
/GAIN
/GAIN
REFS0
R/W
6
0
ADLAR
R/W
Read code
5
0
0x1FE
0x1FF
0x1FF
0x3FF
0x001
0x000
0x201
0x200
...
...
4
0
-
-
Corresponding decimal value
510
1
0
-511
-512
511
511
...
-1
...
MUX3
R/W
3
0
MUX2
R/W
2
0
MUX1
R/W
1
0
MUX0
R/W
0
0
7710E–AVR–08/10
ADMUX