atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 257

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

19.2.2
19.2.3
19.3
19.3.1
7647A–AVR–02/08
Control Register
Voltage Reference for External Devices
Threshold Reference for Internal Analog Comparator
ADC Control and Status Register B– ADCSRB
An external resistor used in conjunction with the Current Source can be used as voltage refer-
ence for external devices. Using a resistor in serie with a lower tolerance than the Current
Source accuracy (≤2%) is recommended.
using standard values of resistors.
An external resistor used in conjunction with the Current Source can be used as threshold refer-
ence for internal Analog Comparator
connected to AIN0 (negative Analog Compare input pin) as well as AIN1 (positive Analog Com-
pare input pin). Using a resistor in serie with a lower tolerance than the Current Source accuracy
(≤2%) is recommended.
values of resistors.
Bit
Read/Write
Initial Value
• Bit 6 – ISRCEN: Current Source Enable
Set this bit to source a 100µA current to the AREF pin.
Clear this bit to disconnect .
• Bit 5 – AREFEN: Analog Reference pin Enable
Set this bit to connect the internal AREF circuit to the AREF pin.
Clear this bit to disconnect the internal AREF circuit from the AREF pin.
ADHSM
R/W
7
0
ISRCEN
Table 19-2
R/W
6
0
AREFEN
R/W
5
0
gives an example of threshold references using standard
(See ”Analog Comparator” on page
Table 19-2
R
4
0
-
ADTS3
R/W
3
0
gives an example of voltage references
ATmega32/64/M1/C1
ADTS2
R/W
2
0
ADTS1
R/W
1
0
258.). This can be
ADTS0
R/W
0
0
ADCSRB
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