AT90PWM81 Atmel Corporation, AT90PWM81 Datasheet - Page 190

• Manufacturer Part Number: AT90PWM81
• Manufacturer: Atmel Corporation

Specifications of AT90PWM81

• Flash (kbytes): 8 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 20
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 125
• Analog Comparators: 3
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.25
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 1
• Output Compare Channels: 8
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

Figure 15-1.
190
BG Calibr ation
Reg isters
BGCC R, BGCRR
BG Calibr ation
Fus es
Aref
AVc c
VPTAT
BG Ref erence
AT90PWM81
Reference Circuitry
AT90PWM81 has an On-chip temperature sensor for monitoring the die temperature. A voltage Propor-
tional-To-Absolute-Temperature, VPTAT, is generated in the voltage reference circuit and after
buffering, is connected to the ADC multiplexer. This temperature sensor can be used for runtime compen-
sation of temperature drift in both the voltage reference and the On-chip Oscillator. To get the absolute
temperature in degrees Kelvin, the measured Vtemp voltage must be scaled with the Vtemp factory cali-
bration value stored in the signature row. See Section “Temperature Measurement”, page 192 for details.
Vbg and Vtemp can be measured with the integrated ADC by selecting the proper ADC channel with
ADMUX (see
SW0
Vbg
SW1
SW2
See “ADC Multiplexer Register – ADMUX” on page
ADC
Comp
SW3
REFS0,REFS1
are used to
control
SW0..3
Voltage Ref e rence
/1.60
/2.13
/3.20
/6.40
Vref
216.).
7734P–AVR–08/10