ATmega16HVA Atmel Corporation, ATmega16HVA Datasheet - Page 117

• Manufacturer Part Number: ATmega16HVA
• Manufacturer: Atmel Corporation

Specifications of ATmega16HVA

• Flash (kbytes): 16 Kbytes
• Pin Count: 28
• Max. Operating Frequency: 4 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 3
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 6
• Adc Resolution (bits): 12
• Adc Speed (ksps): 1.9
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 256
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -20 to 85
• I/o Supply Class: 1.8 to 9.0
• Operating Voltage (vcc): 1.8 to 9.0
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Input Capture Channels: 2
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

21. Voltage Reference and Temperature Sensor
21.1
21.2
8024A–AVR–04/08
Features
Overview
•
•
•
•
•
A low power band-gap reference provides ATmega8HVA/16HVA with an accurate On-chip volt-
age reference V
Voltage Regulator, the V-ADC and the CC-ADC. The reference to the ADCs uses a buffer with
external decoupling capacitor to enable excellent noise performance with minimum power con-
sumption. The reference voltage V
requirement at the current sense input pins. This configuration also enables concurrent opera-
tion of both V-ADC and CC-ADC.
To guarantee ultra low temperature drift after factory calibration, ATmega8HVA/16HVA features
a two-step calibration algorithm. The first step is performed at T
temperature. By default, Atmel factory calibration is performed at T
in the signature row. The value of T
Signature Row from Software” on page 144
second calibration step in their test flow. This requires an accurate input voltage and a stable
room temperature. Temperature drift after this calibration is guaranteed by design and charac-
terization to be less than 90 ppm/°C from -10°C to 70°C. The BG Calibration C Register can also
be altered runtime to implement temperature compensation in software. Very high accuracy for
any temperature inside the temperature range can thus be achieved at the cost of extra calibra-
tion steps.
ATmega8HVA/16HVA has an On-chip temperature sensor for monitoring the die temperature. A
voltage Proportional-To-Absolute-Temperature, V
cuit and connected to the multiplexer at the V-ADC input. This temperature sensor can be used
for runtime compensation of temperature drift in both the voltage reference and the On-chip
Oscillator. To get the absolute temperature in degrees Kelvin, the measured V
be scaled with the VPTAT factory calibration value stored in the signature row.
“26.2.5” on page 144.
Accurate Voltage Reference of 1.100V
Internal Temperature Sensor
Possibility for Runtime Compensation of Temperature Drift in Both Voltage Reference and On-
chip Oscillators
External Decoupling for Optimum Noise Performance
Low Power Consumption
REF
of 1.100V. This reference voltage is used as reference for the On-chip
for details.
REF_P
HOT
can also be found in the signature row. See
/V
REF_N
for details. The customer can easily implement the
to the CC-ADC is scaled to match the full scale
PTAT
, is generated in the voltage reference cir-
ATmega8HVA/16HVA
HOT
HOT
°C and the second at room
°C, and the result is stored
PTAT
”Reading the
voltage must
See Section
117