ATtiny15L
37
The Analog to Digital Converter,
Analog Multiplexer and Gain Stages
Feature list:
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10-bit Resolution
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±2 LSB Absolute Accuracy
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0.5 LSB Integral Non-linearity
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Optional Offset Cancellation
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65 - 260 µs Conversion Time
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Up to 15 kSPS
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4 Multiplexed Single Ended Input Channels
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1 Differential Input Channel with Optional Gain of 20x
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2.56V Internal Voltage Reference
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0 - 2.56V Differential Input Voltage Range
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0 - VCC Single Ended Input Voltage Range
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Optional Left Adjustment for ADC Result Readout
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Free Running or Single Conversion Mode
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Interrupt on ADC Conversion Complete
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Sleep Mode Noise Canceler
The ATtiny15L features a 10-bit successive approximation ADC. The ADC is connected to a 4-channel Analog Multiplexer
which allows one differential voltage input and four single-ended voltage inputs constructed from the pins of Port B. The dif-
ferential input (PB3,PB4) is equipped with a programmable gain stage, providing amplification step of 26 dB (20x) on the
differential input voltage before the A/D conversion. The single-ended voltage inputs at PB2..PB5 refer to 0V (GND).
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 25.
An internal reference voltage of nominally 2.56V is provided on-chip and this reference can optionally be externally decou-
pled at the AREF (PB0) pin by a capacitor, for better noise performance. Alternatively, VCC can be used as reference
voltage for single ended channels. There is also an option to use an external voltage reference and turn-off the internal volt-
age reference. These options are selected using the REFS1..0 bits of the ADMUX control register.
