ATMEGA88-20MUR Atmel, ATMEGA88-20MUR Datasheet - Page 37

• Manufacturer Part Number: ATMEGA88-20MUR
• Description: MCU AVR 8K FLASH 20MHZ 32QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA88-20MUR

• 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: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SPI/TWI/USART
• Total Internal Ram Size: 1KB
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 32
• Package Type: MLF EP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2545S–AVR–07/10
The CKDIV8 Fuse determines the initial value of the CLKPS bits. If CKDIV8 is unprogrammed,
the CLKPS bits will be reset to “0000”. If CKDIV8 is programmed, CLKPS bits are reset to
“0011”, giving a division factor of 8 at start up. This feature should be used if the selected clock
source has a higher frequency than the maximum frequency of the device at the present operat-
ing conditions. Note that any value can be written to the CLKPS bits regardless of the CKDIV8
Fuse setting. The Application software must ensure that a sufficient division factor is chosen if
the selected clock source has a higher frequency than the maximum frequency of the device at
the present operating conditions. The device is shipped with the CKDIV8 Fuse programmed.
Table 8-14.
CLKPS3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
Clock Prescaler Select
CLKPS2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
CLKPS1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
CLKPS0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
ATmega48/88/168
Clock Division Factor
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
128
256
16
32
64
1
2
4
8
37