ATmega16M1 Automotive Atmel Corporation, ATmega16M1 Automotive Datasheet - Page 244

• Manufacturer Part Number: ATmega16M1 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega16M1 Automotive

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 27
• Ext Interrupts: 27
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 1
• Can: 1
• Lin: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 125
• Analog Comparators: 4
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 150
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 14
• Input Capture Channels: 1
• Pwm Channels: 10
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

18.8.1
18.8.2
244
Atmel ATmega16/32/64/M1/C1
User Calibration
Manufacturing Calibration
The software calibration requires that a calibration value is measured and stored in a register
or EEPROM for each chip. The software calibration can be done utilizing the formula:
T = { [ (ADCH << 8) | ADCL ] - T
where ADCH & ADCL are the ADC data registers, k is a fixed coefficient and T
perature sensor offset value determined and stored into EEPROM.
One can also use the calibration values available in the signature row
nature Row from Software” on page 289.
The calibration values are determined from values measured during test at room temperature
which is approximatively +25°C and during test at hot temperature which is approximatively
+125°C. Calibration measures are done at V
mode.
There are two algorithms for determining the Centigrade Temperature
formula 1 for ATmega32 up to rev B
formula 2 for ATmega16/64 and ATmega32 rev C.
formula 1: Temp_C = (((ADC_ts - 273)* TS_Gain) / 128) + TS_Offset [Applicable to devices
with 0xFF or 0x42 ('B') in the signature memory at address 0x003F]
formula 2: Temp_C = ((((ADC_ts -(298 - TS_Offset)) * TS_Gain) / 128) + 25 [Applicable to
devices with 0x43 ('C') in the signature memory at address 0x003F]
Where :
Temp_C is the result temperature in degrees centigrade.
ADC_ts is the 10 bit result the ADC returns from reading the temperature sensor.
TS_Gain is the unsigned fixed point 8-bit temperature sensor gain factor in 1/128th units
stored as previously in the signature row at address 0x0007.
TS_Offset is the signed twos complement 7-bit temperature sensor offset reading stored as
previously in the signature row at address 0x0005.
A new parameter has also been stored into the signature row at address (0x003A[Low Byte] -
0x003B [High Byte]) which is the 10-bit ADC reading of the temperature sensor during Hot
testing (+155C in Grade0 or +130C in Grade1).
See section 27.7.10 in the ATmega32M1 Automotive datasheet for details of reading the Sig-
nature Row.
OS
} / k
CC
= 3V and with ADC in internal Vref (2.56V)
See “Reading the Sig-
7647G–AVR–09/11
OS
is the tem-