Rainbow Electronics ATmega163L - Manual (Page 90)

ATmega163(L)
90
Analog to Digital Converter
Feature List:
•
10-bit Resolution
• 0.5 LSB Integral Non-linearity
• ±2 LSB Absolute Accuracy
• 65 - 260 µs Conversion Time
• Up to 15 kSPS at Maximum Resolution
• Up to 76 kSPS at 8-bit Resolution
• Eight Multiplexed Single Ended Input Channels
• Optional Left Adjustment for ADC Result Readout
• 0 - VCC ADC Input Voltage Range
• Selectable 2.56V ADC Reference Voltage
• Free Run or Single Conversion Mode
• Interrupt on ADC Conversion Complete
• Sleep Mode Noise Canceler
The ATmega163 features a 10-bit successive approximation ADC. The ADC is connected to an 8-channel Analog Multi-
plexer which allows each pin of Port A to be used as input for the ADC.
The ADC contains a Sample and Hold Amplifier 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 Figure 57.
The ADC has two separate analog supply voltage pins, AVCC and AGND. AGND must be connected to GND, and the volt-
age on AV
CC
must not differ more than ±0.3V from V
CC
. See the paragraph ADC Noise Canceling Techniques on how to
connect these pins.
Internal reference voltages of nominally 2.56V or AV
CC
are provided on-chip. The 2.56V reference may be externally
decoupled at the AREF pin by a capacitor for better noise perfomance. See “Internal Voltage Reference” on page 26 for a
description of the internal voltage reference.