ATMEGA48-20PJ Atmel, ATMEGA48-20PJ Datasheet - Page 101

• Manufacturer Part Number: ATMEGA48-20PJ
• Description: IC AVR MCU 4K 5V 20MHZ 28-DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA48-20PJ

• 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): 2.7 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)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATMEGA48-24PJ; ATMEGA48-24PJ

2545S–AVR–07/10
Table 14-4
rect PWM mode.
Table 14-4.
Note:
• Bits 5:4 – COM0B1:0: Compare Match Output B Mode
These bits control the Output Compare pin (OC0B) behavior. If one or both of the COM0B1:0
bits are set, the OC0B output overrides the normal port functionality of the I/O pin it is connected
to. However, note that the Data Direction Register (DDR) bit corresponding to the OC0B pin
must be set in order to enable the output driver.
When OC0B is connected to the pin, the function of the COM0B1:0 bits depends on the
WGM02:0 bit setting.
are set to a normal or CTC mode (non-PWM).
Table 14-5.
Table 14-6
mode.
Table 14-6.
COM0A1
COM0B1
COM0B1
0
0
1
1
0
0
1
1
0
0
1
1
1. A special case occurs when OCR0A equals TOP and COM0A1 is set. In this case, the Com-
pare Match is ignored, but the set or clear is done at TOP. See
page 122
shows the COM0A1:0 bit functionality when the WGM02:0 bits are set to phase cor-
shows the COM0B1:0 bit functionality when the WGM02:0 bits are set to fast PWM
Compare Output Mode, Phase Correct PWM Mode
Compare Output Mode, non-PWM Mode
Compare Output Mode, Fast PWM Mode
COM0A0
COM0B0
COM0B0
for more details.
0
1
0
1
0
1
0
1
0
1
0
1
Table 14-5
Description
Normal port operation, OC0A disconnected.
WGM02 = 0: Normal Port Operation, OC0A Disconnected.
WGM02 = 1: Toggle OC0A on Compare Match.
Clear OC0A on Compare Match when up-counting. Set OC0A on
Compare Match when down-counting.
Set OC0A on Compare Match when up-counting. Clear OC0A on
Compare Match when down-counting.
Description
Normal port operation, OC0B disconnected.
Toggle OC0B on Compare Match
Clear OC0B on Compare Match
Set OC0B on Compare Match
Description
Normal port operation, OC0B disconnected.
Reserved
Clear OC0B on Compare Match, set OC0B at BOTTOM,
(non-inverting mode)
Set OC0B on Compare Match, clear OC0B at BOTTOM,
(inverting mode)
shows the COM0B1:0 bit functionality when the WGM02:0 bits
(1)
ATmega48/88/168
(1)
“Phase Correct PWM Mode” on
101