ATmega48PA Atmel Corporation, ATmega48PA Datasheet - Page 252

• Manufacturer Part Number: ATmega48PA
• Manufacturer: Atmel Corporation

Specifications of ATmega48PA

• Flash (kbytes): 4 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• 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: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 256
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

24. Analog-to-Digital Converter
24.1
24.2
8271D–AVR–05/11
Features
Overview
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The ATmega48A/PA/88A/PA/168A/PA/328/P features a 10-bit successive approximation ADC.
The ADC is connected to an 8-channel Analog Multiplexer which allows eight single-ended volt-
age inputs constructed from the pins of Port A. The single-ended voltage inputs refer to 0V
(GND).
The ADC contains a Sample and Hold circuit which ensures that the input voltage to the ADC is
held at a constant level during conversion. A block diagram of the ADC is shown in
on page
The ADC has a separate analog supply voltage pin, AV
from V
Internal reference voltages of nominally 1.1V or AV
ence may be externally decoupled at the AREF pin by a capacitor for better noise performance.
The Power Reduction ADC bit, PRADC, in
be disabled by writing a logical zero to enable the ADC.
The ADC converts an analog input voltage to a 10-bit digital value through successive approxi-
mation. The minimum value represents GND and the maximum value represents the voltage on
the AREF pin minus 1 LSB. Optionally, AV
nected to the AREF pin by writing to the REFSn bits in the ADMUX Register. The internal
voltage reference may thus be decoupled by an external capacitor at the AREF pin to improve
noise immunity.
10-bit Resolution
0.5 LSB Integral Non-linearity
± 2 LSB Absolute Accuracy
13 - 260µs Conversion Time
Up to 76.9kSPS (Up to 15kSPS at Maximum Resolution)
6 Multiplexed Single Ended Input Channels
2 Additional Multiplexed Single Ended Input Channels (TQFP and QFN/MLF Package only)
Temperature Sensor Input Channel
Optional Left Adjustment for ADC Result Readout
0 - V
Selectable 1.1V ADC Reference Voltage
Free Running or Single Conversion Mode
Interrupt on ADC Conversion Complete
Sleep Mode Noise Canceler
CC
CC
253.
ADC Input Voltage Range
. See the paragraph
ATmega48A/PA/88A/PA/168A/PA/328/P
”ADC Noise Canceler” on page 258
CC
”Minimizing Power Consumption” on page 43
or an internal 1.1V reference voltage may be con-
CC
CC
are provided On-chip. The voltage refer-
. AV
CC
must not differ more than ±0.3V
on how to connect this pin.
Figure 24-1
must
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