ATtiny25 Automotive Atmel Corporation, ATtiny25 Automotive Datasheet - Page 90

• Manufacturer Part Number: ATtiny25 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATtiny25 Automotive

• Flash (kbytes): 2 Kbytes
• Pin Count: 8
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• 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): 0.12
• Eeprom (bytes): 128
• 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: 2
• Output Compare Channels: 5
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

14.1.11
90
ATtiny25/45/85
Timer/Counter1 in PWM Mode
When the PWM mode is selected, Timer/Counter1 and the Output Compare Register C -
OCR1C form a dual 8-bit, free-running and glitch-free PWM generator with outputs on the
PB1(OC1A) and PB3(OC1B) pins and inverted outputs on pins PB0(OC1A) and PB2(OC1B). As
default non-overlapping times for complementary output pairs are zero, but they can be inserted
using a Dead Time Generator (see description on page 100).
Figure 14-4. The PWM Output Pair
When the counter value match the contents of OCR1A or OCR1B, the OC1A and OC1B outputs
are set or cleared according to the COM1A1/COM1A0 or COM1B1/COM1B0 bits in the
Timer/Counter1 Control Register A - TCCR1, as shown in
Timer/Counter1 acts as an up-counter, counting from $00 up to the value specified in the output
compare register OCR1C, and starting from $00 up again. A compare match with OC1C will set
an overflow interrupt flag (TOV1) after a synchronization delay following the compare event.
Table 14-4.
Note that in PWM mode, writing to the Output Compare Registers OCR1A or OCR1B, the data
value is first transferred to a temporary location. The value is latched into OCR1A or OCR1B
when the Timer/Counter reaches OCR1C. This prevents the occurrence of odd-length PWM
pulses (glitches) in the event of an unsynchronized OCR1A or OCR1B. See
example.
COM11
0
0
1
1
PWM1x
PWM1x
Compare Mode Select in PWM Mode
t
non-overlap
COM10
0
1
0
1
=0
Effect on Output Compare Pins
OC1x not connected.
OC1x not connected.
OC1x cleared on compare match. Set whenTCNT1 = $01.
OC1x set on compare match. Cleared when TCNT1 = $00.
OC1x cleared on compare match. Set when TCNT1 = $01.
OC1x not connected.
OC1x Set on compare match. Cleared when TCNT1= $01.
OC1x not connected.
t
non-overlap
=0
x = A or B
Table
14-4.
Figure 14-5
7598H–AVR–07/09
for an