ATtiny85 Atmel Corporation, ATtiny85 Datasheet - Page 43

• Manufacturer Part Number: ATtiny85
• Manufacturer: Atmel Corporation

Specifications of ATtiny85

• Flash (kbytes): 8 Kbytes
• Pin Count: 8
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 3
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 6
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 5
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

8.2.3
8.2.4
2586N–AVR–04/11
Brown-out Detection
Watchdog Reset
Figure 8-4.
ATtiny25/45/85 has an On-chip Brown-out Detection (BOD) circuit for monitoring the V
during operation by comparing it to a fixed trigger level. The trigger level for the BOD can be
selected by the BODLEVEL Fuses. The trigger level has a hysteresis to ensure spike free
Brown-out Detection. The hysteresis on the detection level should be interpreted as V
V
When the BOD is enabled, and V
8-5), the Brown-out Reset is immediately activated. When V
(V
expired.
The BOD circuit will only detect a drop in V
ger than t
Figure 8-5.
When the Watchdog times out, it will generate a short reset pulse of one CK cycle duration. On
the falling edge of this pulse, the delay timer starts counting the Time-out period t
“Watchdog Timer” on page 44
BOT
BOT+
+ V
in
HYST
BOD
Figure
CC
/2 and V
given in
External Reset During Operation
Brown-out Reset During Operation
INTERNAL
TIME-OUT
8-5), the delay counter starts the MCU after the Time-out period t
RESET
RESET
V
CC
BOT-
“System and Reset Characteristics” on page
= V
BOT
for details on operation of the Watchdog Timer.
- V
CC
HYST
decreases to a value below the trigger level (V
V
BOT-
/2.
CC
if the voltage stays below the trigger level for lon-
CC
V
t
TOUT
BOT+
increases above the trigger level
170.
ATtiny25/45/85
TOUT
BOT-
. Refer to
TOUT
in
CC
BOT+
Figure
level
has
43
=