ATmega162 Atmel Corporation, ATmega162 Datasheet - Page 52

• Manufacturer Part Number: ATmega162
• Manufacturer: Atmel Corporation

Specifications of ATmega162

• Flash (kbytes): 16 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 35
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 6
• Input Capture Channels: 2
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Internal Voltage
Reference
Voltage Reference
Enable Signals and
Start-up Time
Watchdog Timer
52
ATmega162/V
• Bit 2 – BORF: Brown-out Reset Flag
This bit is set if a Brown-out Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 1 – EXTRF: External Reset Flag
This bit is set if an External Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 0 – PORF: Power-on Reset Flag
This bit is set if a Power-on Reset occurs. The bit is reset only by writing a logic zero to the flag.
To make use of the Reset Flags to identify a reset condition, the user should read and then
Reset the MCUCSR as early as possible in the program. If the register is cleared before another
reset occurs, the source of the Reset can be found by examining the Reset Flags.
ATmega162 features an internal bandgap reference. This reference is used for Brown-out
Detection, and it can be used as an input to the Analog Comparator.
The voltage reference has a start-up time that may influence the way it should be used. The
start-up time is given in
erence is on during the following situations:
1. When the BOD is enabled (by programming the BODLEVEL Fuses).
2. When the bandgap reference is connected to the Analog Comparator (by setting the
Thus, when the BOD is not enabled, after setting the ACBG bit, the user must always allow the
reference to start up before the output from the Analog Comparator is used. To reduce power
consumption in Power-down mode, the user can avoid the two conditions above to ensure that
the reference is turned off before entering Power-down mode.
Table 21. Internal Voltage Reference Characteristics
The Watchdog Timer is clocked from a separate On-chip Oscillator which runs at 1 MHz. This is
the typical frequency at V
els. By controlling the Watchdog Timer prescaler, the Watchdog Reset interval can be adjusted
as shown in
dog Timer. The Watchdog Timer is also reset when it is disabled and when a Chip Reset occurs.
Eight different clock cycle periods can be selected to determine the reset period. If the reset
period expires without another Watchdog Reset, the ATmega162 resets and executes from the
Reset Vector. For timing details on the Watchdog Reset, refer to
To prevent unintentional disabling of the Watchdog or unintentional change of time-out period, 3
different safety levels are selected by the Fuses M161C and WDTON as shown in Table 22.
Safety level 0 corresponds to the setting in ATmega161. There is no restriction on enabling the
Symbol
V
t
I
ACBG bit in ACSR).
BG
BG
BG
Parameter
Bandgap reference voltage
Bandgap reference start-up time
Bandgap reference current
consumption
Table 23 on page
Table
CC
= 5V. See characterization data for typical values at other V
21. To save power, the reference is not always turned on. The ref-
54. The WDR – Watchdog Reset – instruction resets the Watch-
Min.
1.05
Typ.
1.10
40
10
page
Max.
1.15
70
54.
Units
µA
µs
V
2513K–AVR–07/09
CC
lev-