236
ATmega16M1/32M1/64M1 [DATASHEET]
8209E–AVR–11/2012
Bit 7 – AMP0EN: Amplifier 0 Enable Bit
Set this bit to enable the Amplifier 0.
Clear this bit to disable the Amplifier 0.
Clearing this bit while a conversion is running will take effect at the end of the conversion.
Warning: Always clear AMP0TS0:1 when clearing AMP0EN.
Bit 6 – AMP0IS: Amplifier 0 Input Shunt
Set this bit to short-circuit the Amplifier 0 input.
Clear this bit to normally use the Amplifier 0.
Bit 5:4 – AMP0G[1:0]: Amplifier 0 Gain Selection Bits
These two bits determine the gain of the amplifier 0.
To ensure an accurate result, after the gain value has been changed, the amplifier input needs to have a quite sta-
ble input value during at least four Amplifier synchronization clock periods.
Bit 3 – AMPCMP0: Amplifier 0 - Comparator 0 connection
Set this bit to connect the amplifier 0 to the comparator 0 positive input. In this configuration the comparator clock
is adapted to the amplifier clock and AMP0TS[2:0] bits have no effect.
Clear this bit to normally use the Amplifier 0.
Bit 2:0 – AMP0TS[2:0]: Amplifier 0 Clock Source Selection Bits
In accordance with the
Table 21-9 on page 236, these three bits select the event which will generate the clock for
the amplifier 0. This clock source is necessary to start the conversion on the amplified channel.
Table 21-8.
Amplifier 0 gain selection.
AMP0G[1:0]
Description
00
Gain 5
01
Gain 10
10
Gain 20
11
Gain 40
Table 21-9.
AMP0 clock source selection.
AMP0TS[2:0]
Clock source
000
ADC Clock/8
001
Timer/Counter0 compare match
010
Timer/Counter0 overflow
011
Timer/Counter1 compare Match B
100
Timer/Counter1 overflow
101
PSC Module 0 synchronization signal (PSS0)
110
PSC Module 1 synchronization signal (PSS1)
111
PSC Module 2 synchronization signal (PSS2)