ATtiny24A Atmel Corporation, ATtiny24A Datasheet - Page 40

• Manufacturer Part Number: ATtiny24A
• Manufacturer: Atmel Corporation

Specifications of ATtiny24A

• Flash (kbytes): 2 Kbytes
• Pin Count: 14
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 12
• Ext Interrupts: 12
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• 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: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

8.2.2
8.2.3
40
ATtiny24A/44A/84A
External Reset
Brown-out Detection
An External Reset is generated by a low level on the RESET pin if enabled. Reset pulses longer
than the minimum pulse width (see
ate a reset, even if the clock is not running. Shorter pulses are not guaranteed to generate a
reset. When the applied signal reaches the Reset Threshold Voltage – V
edge, the delay counter starts the MCU after the Time-out period – t
Figure 8-4.
ATtiny24A/44A/84A has an On-chip Brown-out Detection (BOD) circuit for monitoring the V
level 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 on page
trigger level (V
out period t
The BOD circuit will only detect a drop in V
ger than t
Figure 8-5.
BOT
+ V
INTERNAL
TIME-OUT
HYST
BOD
RESET
RESET
TOUT
CC
V
40), the Brown-out Reset is immediately activated. When V
/2 and V
given in
CC
BOT+
External Reset During Operation
has expired.
Brown-out Reset During Operation
in
BOT-
Figure 8-5 on page
“System and Reset Characteristics” on page
= V
BOT
- V
CC
“System and Reset Characteristics” on page
V
HYST
decreases to a value below the trigger level (V
BOT-
/2.
40), the delay counter starts the MCU after the Time-
CC
if the voltage stays below the trigger level for lon-
V
t
TOUT
BOT+
176.
TOUT
CC
– has expired.
RST
increases above the
– on its positive
176) will gener-
8183D–AVR–04/11
BOT-
in
BOT+
Figure
CC
=