ATTIny13-12PI ATMEL Corporation, ATTIny13-12PI Datasheet - Page 84

• Manufacturer Part Number: ATTIny13-12PI
• Description: 8-bit AVR Microcontroller with 1K Bytes In-System Programmable Flash
• Manufacturer: ATMEL Corporation

ADC Voltage Reference
ADC Noise Canceler
84
ATtiny13
The reference voltage for the ADC (V
Single ended channels that exceed V
selected as either V
conversion result after switching reference voltage source may be inaccurate, and the
user is advised to discard this result.
The ADC features a noise canceler that enables conversion during sleep mode to
reduce noise induced from the CPU core and other I/O peripherals. The noise canceler
can be used with ADC Noise Reduction and Idle mode. To make use of this feature, the
following procedure should be used:
Note that the ADC will not be automatically turned off when entering other sleep modes
than Idle mode and ADC Noise Reduction mode. The user is advised to write zero to
ADEN before entering such sleep modes to avoid excessive power consumption.
1. Make sure that the ADC is enabled and is not busy converting. Single Con-
2. Enter ADC Noise Reduction mode (or Idle mode). The ADC will start a con-
3. If no other interrupts occur before the ADC conversion completes, the ADC
version mode must be selected and the ADC conversion complete interrupt
must be enabled.
version once the CPU has been halted.
interrupt will wake up the CPU and execute the ADC Conversion Complete
interrupt routine. If another interrupt wakes up the CPU before the ADC con-
version is complete, that interrupt will be executed, and an ADC Conversion
Complete interrupt request will be generated when the ADC conversion
completes. The CPU will remain in active mode until a new sleep command
is executed.
CC
, or internal 1.1V reference, or external AREF pin. The first ADC
REF
REF
will result in codes close to 0x3FF. V
) indicates the conversion range for the ADC.
2535B–AVR–01/04
REF
can be