ATmega162 datasheet(195/324 Pages) ATMEL

195 / 324 page

195

2513K–AVR–07/09

ATmega162/V

Analog

Comparator

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’s output can be set to trigger

the Timer/Counter1 Input Capture function. In addition, the comparator can trigger a separate

interrupt, exclusive to the Analog Comparator. The user can select Interrupt triggering on com-

parator output rise, fall or toggle. A block diagram of the comparator and its surrounding logic is

shown in Figure 82

Figure 82. Analog Comparator Block Diagram(1)

Note:

1. Refer to Figure 1 on page 2 and Table 32 on page 72 for Analog Comparator pin placement.

Analog Comparator

Control and Status

• Bit 7 – ACD: Analog Comparator Disable

When this bit is written logic one, the power to the Analog Comparator is switched off. This bit

can be set at any time to turn off the Analog Comparator. This will reduce power consumption in

Active and Idle mode. When changing the ACD bit, the Analog Comparator Interrupt must be

disabled by clearing the ACIE bit in ACSR. Otherwise an interrupt can occur when the bit is

changed.

• Bit 6 – ACBG: Analog Comparator Bandgap Select

When this bit is set, a fixed bandgap reference voltage replaces the positive input to the Analog

Comparator. When this bit is cleared, AIN0 is applied to the positive input of the Analog Compar-

ator. When the bandgap reference is used as input to the Analog Comparator, it will take a

certain time for the voltage to stabilize. If not stibilized, the first conversion may give a wrong

value. See “Internal Voltage Reference” on page 52.

• Bit 5 – ACO: Analog Comparator Output

The output of the Analog Comparator is synchronized and then directly connected to ACO. The

synchronization introduces a delay of 1 - 2 clock cycles.

ACBG

BANDGAP

REFERENCE

Bit

765

4321

ACD

ACBG

ACO

ACI

ACIE

ACIC

ACIS1

ACIS0

ACSR

Read/Write

R/W

Initial Value

N/A

0000

ATmega162 Datasheet(PDF) 195 Page - ATMEL Corporation

ATmega162 Datasheet(HTML) 195 Page - ATMEL Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL