Datasheet

213
8018P–AVR–08/10
ATmega169P
21.1 Analog Comparator Multiplexed Input
It is possible to select any of the ADC7:0 pins to replace the negative input to the Analog Com-
parator. The ADC multiplexer is used to select this input, and consequently, the ADC must be
switched off to utilize this feature. If the Analog Comparator Multiplexer Enable bit (ACME in
ADCSRB) is set and the ADC is switched off (ADEN in ADCSRA is zero), MUX2:0 in ADMUX
select the input pin to replace the negative input to the Analog Comparator, as shown in Table
21-1. If ACME is cleared or ADEN is set, AIN1 is applied to the negative input to the Analog
Comparator.
Table 21-1. Analog Comparator Multiplexed Input
ACME ADEN MUX2:0 Analog Comparator Negative Input
0 x xxx AIN1
1 1 xxx AIN1
1 0 000 ADC0
1 0 001 ADC1
1 0 010 ADC2
1 0 011 ADC3
1 0 100 ADC4
1 0 101 ADC5
1 0 110 ADC6
1 0 111 ADC7