ATmega8535 Atmel Corporation, ATmega8535 Datasheet - Page 218

• Manufacturer Part Number: ATmega8535
• Manufacturer: Atmel Corporation

Specifications of ATmega8535

• Flash (kbytes): 8 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

ADC Conversion Result
218
ATmega8535(L)
After the conversion is complete (ADIF is high), the conversion result can be found in
the ADC Result Registers (ADCL, ADCH).
For single ended conversion, the result is
where V
ence (see Table 84 on page 219 and Table 85 on page 220). 0x000 represents analog
ground, and 0x3FF represents the selected reference voltage minus one LSB.
If differential channels are used, the result is
where V
input pin, GAIN the selected gain factor, and V
result is presented in two’s complement form, from 0x200 (-512d) through 0x1FF
(+511d). Note that if the user wants to perform a quick polarity check of the results, it is
sufficient to read the MSB of the result (ADC9 in ADCH). If the bit is one, the result is
negative, and if the bit is zero, the result is positive. Figure 111 shows the decoding of
the differential input range.
Table 83 shows the resulting output codes if the differential input channel pair (ADCn -
ADCm) is selected with a gain of GAIN and a reference voltage of V
Figure 111. Differential Measurement Range
- V
REF
/GAIN
IN
POS
is the voltage on the selected input pin and V
is the voltage on the positive input pin, V
ADC
=
(
----------------------------------------------------------------------- -
Output Code
V
0x3FF
POS
0x1FF
0x000
ADC
–
0
V
0x200
NEG
=
V
REF
V
--------------------------
) GAIN 512
IN
⋅
V
⋅
REF
REF
1024
the selected voltage reference. The
⋅
NEG
REF
the voltage on the negative
the selected voltage refer-
V
REF
REF
/GAIN Differential Input
.
Voltage (Volts)
2502K–AVR–10/06