ATMEGA48PA-PU Atmel, ATMEGA48PA-PU Datasheet - Page 33

• Manufacturer Part Number: ATMEGA48PA-PU
• Description: MCU AVR 4KB FLASH IND 28PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA48PA-PU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Processor Series: ATMEGA48x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: 2-Wire, SPI, USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 23
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 6 Channel
• On-chip Dac: 10 bit, 6 Channel
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVR
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.6
8271C–AVR–08/10
Calibrated Internal RC Oscillator
Table 8-9.
Table 8-10.
Note:
By default, the Internal RC Oscillator provides an approximate 8.0 MHz clock. Though voltage
and temperature dependent, this clock can be very accurately calibrated by the user. See
28-10 on page 322
See
This clock may be selected as the system clock by programming the CKSEL Fuses as shown in
Table
the pre-programmed calibration value into the OSCCAL Register and thereby automatically cali-
brates the RC Oscillator. The accuracy of this calibration is shown as Factory calibration in
28-10 on page
By changing the OSCCAL register from SW, see
page
The accuracy of this calibration is shown as User calibration in
When this Oscillator is used as the chip clock, the Watchdog Oscillator will still be used for the
Watchdog Timer and for the Reset Time-out. For more information on the pre-programmed cali-
bration value, see the section
Table 8-11.
Notes:
ATmega48A/48PA/88A/88PA/168A/168PA/328/328
CKSEL3...
SUT1...0
0100
0101
”System Clock Prescaler” on page 36
01
10
11
37, it is possible to get a higher calibration accuracy than by using the factory calibration.
0
8-11. If selected, it will operate with no external components. During reset, hardware loads
(1)
1. This option should only be used if frequency stability at start-up is not important for the
1. The device is shipped with this option selected.
2. If 8 MHz frequency exceeds the specification of the device (depends on V
application
Frequency Range
Fuse can be programmed in order to divide the internal frequency by 8.
Start-up Times for the Low-frequency Crystal Oscillator Clock Selection
Start-up Times for the Low-frequency Crystal Oscillator Clock Selection
Internal Calibrated RC Oscillator Operating Modes
Additional Delay from Reset (V
322.
for more details. The device is shipped with the CKDIV8 Fuse programmed.
7.3 - 8.1
Power-down and Power-save
Start-up Time from
4 CK + 4.1 ms
4 CK + 65 ms
(2)
”Calibration Byte” on page
32K CK
(MHz)
1K CK
for more details.
CC
= 5.0V)
”OSCCAL – Oscillator Calibration Register” on
Reserved
Recommended Usage
Slowly rising power
Stable frequency at start-up
Recommended Usage
Stable frequency at start-up
301.
Table 28-10 on page
CKSEL3...0
0010
(1)
CC
), the CKDIV8
322.
Table
Table
33