ATMEGA406-1AAU Atmel, ATMEGA406-1AAU Datasheet - Page 123

• Manufacturer Part Number: ATMEGA406-1AAU
• Description: IC AVR MCU 40K 1MHZ 48LQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA406-1AAU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 1MHz
• Connectivity: I²C
• Peripherals: POR, WDT
• Number Of I /o: 18
• Program Memory Size: 40KB (20K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 25 V
• Data Converters: A/D 10x12b
• Oscillator Type: Internal
• Operating Temperature: -30°C ~ 85°C
• Package / Case: 48-LQFP
• Processor Series: ATMEGA48x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: 2-Wire
• Maximum Clock Frequency: 1 MHz
• Number Of Programmable I/os: 18
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 30 C
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 1MHz
• Total Internal Ram Size: 2KB
• # I/os (max): 18
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 5/9/12/15/18/24V
• Operating Supply Voltage (max): 25V
• Operating Supply Voltage (min): 4V
• On-chip Adc: 10-chx12-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -30C to 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 48
• Package Type: LQFP
• Controller Family/series: AVR MEGA
• No. Of I/o's: 18
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 2KB
• Cpu Speed: 1MHz
• Rohs Compliant: Yes
• For Use With: 770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPI
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

21.3
21.3.1
21.3.2
2548E–AVR–07/06
Register Description for Voltage Reference and Temperature Sensor
BGCCR – Bandgap Calibration C Register
BGCRR – Bandgap Calibration R Register
• Bit 7 - BGEN
This bit is not available from revision E and on of the ATmega406. A complete description is
found in the revision A of this document.
• Bit 6 – Res: Reserved Bit
This bit is reserved for future use.
• Bit 5:0 – BGCC5:0: BG Calibration of PTAT Current
These bits are used for trimming of the nominal value of the bandgap reference voltage. These
bits are binary coded. Minimum VREF: 000000, maximum VREF: 111111. Step size approxi-
mately 2 mV.
• Bit 7:0 – BGCR7:0: BG Calibration of Resistor ladder
These bits are used for temperature gradient adjustment of the bandgap reference.
illustrates VREF as a function of temperature. VREF has a positive temperature coefficient at
low temperatures and negative temperature coefficient at high temperatures. Depending on the
process variations, the top of the VREF curve may be located at higher or lower temperatures.
To minimize the temperature drift in the temperature range of interest, BGCRR is used to adjust
the top of the curve towards the centre of the temperature range of interest. The BGCRR bits are
temperature coded resulting in 9 possible settings: 00000000, 00000001, 00000011, 00000111,
… , 11111111. The value 00000000 shifts the top of the VREF curve to the highest possible
temperature, and the value 11111111 shifts the top of the VREF curve to the lowest possible
temperature.
Bit
(0xD0)
Read/Write
Initial Value
Bit
(0xD1)
Read/Write
Initial Value
BGCR7
BGEN
R/W
R
7
0
7
0
BGCR6
R/W
R
6
–
0
6
0
BGCC5
BGCR5
R/W
R/W
5
0
5
0
BGCC4
BGCR4
R/W
R/W
0
0
4
4
BGCC3
BGCR3
R/W
R/W
3
0
3
0
BGCC2
BGCR2
R/W
R/W
2
0
2
0
BGCC1
BGCR1
R/W
R/W
1
0
1
0
ATmega406
BGCC0
BGCR0
R/W
R/W
0
0
0
0
Figure 21-2
BGCRR
BGCCR
123