ATA5771 ATMEL Corporation, ATA5771 Datasheet - Page 181

• Manufacturer Part Number: ATA5771
• Manufacturer: ATMEL Corporation

15. Analog Comparator
15.1
8006G–AVR–01/08
Analog Comparator Multiplexed Input
The Analog Comparator compares the input values on the positive pin AIN0 and negative pin
AIN1. When the voltage on the positive pin AIN0 is higher than the voltage on the negative pin
AIN1, the Analog Comparator output, ACO, is set. The comparator can trigger a separate inter-
rupt, exclusive to the Analog Comparator. The user can select Interrupt triggering on comparator
output rise, fall or toggle. A block diagram of the comparator and its surrounding logic is shown
in
Figure 15-1. Analog Comparator Block Diagram
Notes:
See
When the Analog to Digital Converter (ADC) is configurated as single ended input channel, it is
possible to select any of the ADC7..0 pins to replace the negative input to the Analog Compara-
tor. 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), MUX1..0 in ADMUX
select the input pin to replace the negative input to the Analog Comparator, as shown in
15-1. If ACME is cleared or ADEN is set, AIN1 is applied to the negative input to the Analog
Comparator.
Table 15-1.
Figure
ADC MULTIPLEXER
ACME
Figure 1-1 on page 2
REFERENCE
ACME
ADEN
0
1
1
1
1
1
BANDGAP
OUTPUT
1. See
15-1.
(1)
Analog Comparator Multiplexed Input
ACBG
Table 15-1 on page
ADEN
X
1
0
0
0
0
and
MUX4..0
XXXXX
XXXXX
Table 10-9 on page 66
00000
00001
00010
00011
129.
Analog Comparator Negative Input
AIN1
AIN1
ADC0
ADC1
ADC2
ADC3
for Analog Comparator pin placement.
ATtiny24/44/84
ACIC
To T/C1 Capture
Trigger MUX
Table
129