ATMEGA48-20AU Atmel, ATMEGA48-20AU Datasheet - Page 362
Manufacturer Part Number
IC AVR MCU 4K 20MHZ 5V 32TQFP
Specifications of ATMEGA48-20AU
I²C, SPI, UART/USART
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
Program Memory Size
4KB (2K x 16)
Program Memory Type
256 x 8
512 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
-40°C ~ 85°C
Package / Case
Data Bus Width
Data Ram Size
Maximum Clock Frequency
Number Of Programmable I/os
Number Of Timers
Operating Supply Voltage
2.7 V to 5.5 V
Maximum Operating Temperature
+ 85 C
3rd Party Development Tools
Development Tools By Supplier
ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
Minimum Operating Temperature
- 40 C
8-ch x 10-bit
Device Core Size
Total Internal Ram Size
# I/os (max)
Number Of Timers - General Purpose
Operating Supply Voltage (typ)
Operating Supply Voltage (max)
Operating Supply Voltage (min)
Instruction Set Architecture
Operating Temp Range
-40C to 85C
Operating Temperature Classification
For Use With
ATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFPATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEM
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
- Two succeeding resets are applied where the second reset occurs in the 10 ns window
before the device is out of the reset-state caused by the first reset.
- A reset is applied in a 10 ns window while the system clock prescaler value is updated by
- Leaving SPI-programming mode generates an internal reset signal that can trigger this
The two first cases can occur during normal operating mode, while the last case occurs only
during programming of the device.
The first case can be avoided during run-mode by ensuring that only one reset source is
active. If an external reset push button is used, the reset start-up time should be selected
such that the reset line is fully debounced during the start-up time.
The second case can be avoided by not using the system clock prescaler.
The third case occurs during In-System programming only. It is most frequently seen when
using the internal RC at maximum frequency.
If the device gets stuck in the reset-state, turn power off, then on again to get the device out
of this state.
2. Interrupts may be lost when writing the timer registers in the asynchronous timer
The interrupt will be lost if a timer register that is synchronous timer clock is written when the
asynchronous Timer/Counter register (TCNTx) is 0x00.
Always check that the asynchronous Timer/Counter register neither have the value 0xFF nor
0x00 before writing to the asynchronous Timer Control Register (TCCRx), asynchronous
Timer Counter Register (TCNTx), or asynchronous Output Compare Register (OCRx).