ATMEGA8HVD-4MX Atmel, ATMEGA8HVD-4MX Datasheet - Page 23

• Manufacturer Part Number: ATMEGA8HVD-4MX
• Description: MCU AVR 8K FLASH 2.1-8V 4MHZ QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8HVD-4MX

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 2.4 V
• Data Converters: A/D 1x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 18-MLF® Exposed Pad (Staggered Leads), DFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Connectivity: -

8.1.5
8.2
8.3
8052B–AVR–09/08
Clock Sources
Calibrated Fast RC Oscillator
Watchdog Timer and Battery Protection Clock
ADC. The dedicated ADC clock allows halting the CPU and I/O clocks in order to reduce noise
generated by digital circuitry. This gives more accurate ADC conversion results.
The Watchdog Timer and Current Protection are provided with a dedicated clock domain. This
allows operation in all modes except Power-off. It also allows low power operation by utilizing
a Ultra Low Power Oscillator dedicated to this purpose.
The following section describe the clock sources available in the device. The clocks are input
to the AVR clock generator, and routed to the appropriate modules.
The calibrated Fast RC Oscillator by default provides a 8.0 MHz clock to the system clock
prescaler. The frequency is nominal value at 85
components. With an accurate time reference and by using runtime calibration, this oscillator
can be calibrated to an accuracy of ± 1% over the entire temperature range. During reset,
hardware loads the calibration byte into the FOSCCAL Register and thereby automatically cal-
ibrates the Fast RC Oscillator. At 85
oscillator can be calibrated to any frequency in the range 7.3- 8.1 MHz by changing the FOS-
CCAL register. For more information on the pre-programmed calibration value, see the section
”Reading the Signature Row from Software” on page
tem clock is given by the
When this Oscillator is selected, start-up times are determined by the SUT Fuses as shown in
Table 8-1 on page
Table 8-1.
Notes:
SUT3..0
111
000
001
010
011
100
101
110
1. The device is shipped with this option selected.
2. The actual value of the added, selectable 4- 512 ms delay depends on the actual frequency
(1)
of the
cal Characteristics” on page 142
Start-up times for the calibrated Fast RC Oscillator clock selection
”Ultra Low Power RC Oscillator” on page
23.
Start-up Time from
”System Clock Prescaler” on page
Power-save
6 CK
6 CK
6 CK
6 CK
6 CK
6 CK
6 CK
6 CK
°
C, this calibration gives a frequency of 8 MHz ± 4%. The
Additional Delay from Reset, Typical Values
°
C. This clock will operate with no external
124. Note that the frequency of the sys-
24. See
ATmega4HVD/8HVD
25.
14 CK + 128 ms
14 CK + 256 ms
14 CK + 512 ms
Table 8-2 on page 25
14 CK + 16 ms
14 CK + 32 ms
14 CK + 64 ms
14 CK + 4 ms
14 CK + 8 ms
and
”Electri-
(2)
23