atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 258

• Manufacturer Part Number: atmega32c1
• Description: Atmega32m1 Automotive 8-bit Avr Microcontroller With 32k/64k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

20. Analog Comparator
20.1
20.2
258
Features
Overview
ATmega32/64/M1/C1
The Analog Comparator compares the input values on the positive pin ACMPx and negative pin
ACMPM or ACMPMx.
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The ATmega32/64/M1/C1 features 4 fast analog comparators.
Each comparator has a dedicated input on the positive input, and the negative input of each
comparator can be configured as:
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When the voltage on the positive ACMPn pin is higher than the voltage selected by the ACnM
multiplexer on the negative input, the Analog Comparator output, ACnO, is set.
The comparator is a clocked comparator. A new comparison is done on the falling edge of
CLK
tus Register – ACSR” on page
Each comparator can trigger a separate interrupt, exclusive to the Analog Comparator. In addi-
tion, the user can select Interrupt triggering on comparator output rise, fall or toggle.
The interrupt flags can also be used to synchronize ADC or DAC conversions.
Moreover, the comparator’s output of the comparator 1 can be set to trigger the Timer/Counter1
Input Capture function.
A block diagram of the four comparators and their surrounding logic is shown in
4 Analog Comparators
High Speed Clocked Comparators
+/-30mV Hysteresys
4 reference levels
Generation of Configurable Interrupts
a steady value among the 4 internal reference levels defined by the Vref selected thanks to
the REFS1:0 bits in ADMUX register.
a value generated from the internal DAC
an external analog input ACMPMx.
I/O
or CLK
I/O
/2 ( Depending on ACCKDIV fit of ACSR register,
264.).
See “Analog Comparator Sta-
Figure
7647A–AVR–02/08
20-1.