ATtiny85 Atmel Corporation, ATtiny85 Datasheet - Page 75
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ATtiny85
Manufacturer Part Number
ATtiny85
Description
Manufacturer
Atmel Corporation
Datasheets
1.ATTINY25.pdf
(34 pages)
2.ATTINY25.pdf
(34 pages)
3.ATTINY25.pdf
(30 pages)
4.ATTINY85.pdf
(234 pages)
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
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
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Part Number:
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Manufacturer:
ATMEL
Quantity:
30
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Part Number:
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Manufacturer:
CUI
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1 000
Part Number:
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Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
ATtiny85V-10SH
Manufacturer:
Intel
Quantity:
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Part Number:
ATtiny85V-10SU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
11.7.3
2586N–AVR–04/11
Fast PWM Mode
ning with none or a low prescaler value must be done with care since the CTC mode does not
have the double buffering feature. If the new value written to OCR0A is lower than the current
value of TCNT0, the counter will miss the Compare Match. The counter will then have to count to
its maximum value (0xFF) and wrap around starting at 0x00 before the Compare Match can
occur.
For generating a waveform output in CTC mode, the OC0A output can be set to toggle its logical
level on each Compare Match by setting the Compare Output mode bits to toggle mode
(COM0A[1:0] = 1). The OC0A value will not be visible on the port pin unless the data direction
for the pin is set to output. The waveform generated will have a maximum frequency of f
f
equation:
The N variable represents the prescale factor (1, 8, 64, 256, or 1024).
As for the Normal mode of operation, the TOV0 Flag is set in the same timer clock cycle that the
counter counts from MAX to 0x00.
The fast Pulse Width Modulation or fast PWM mode (WGM0[2:0] = 3 or 7) provides a high fre-
quency PWM waveform generation option. The fast PWM differs from the other PWM option by
its single-slope operation. The counter counts from BOTTOM to TOP then restarts from BOT-
TOM. TOP is defined as 0xFF when WGM0[2:0] = 3, and OCR0A when WGM0[2:0] = 7.
In non-inverting Compare Output mode, the Output Compare (OC0x) is cleared on the Compare
Match between TCNT0 and OCR0x, and set at BOTTOM. In inverting Compare Output mode,
the output is set on Compare Match and cleared at BOTTOM.
Due to the single-slope operation, the operating frequency of the fast PWM mode can be twice
as high as the phase correct PWM mode that use dual-slope operation. This high frequency
makes the fast PWM mode well suited for power regulation, rectification, and DAC applications.
High frequency allows physically small sized external components (coils, capacitors), and there-
fore reduces total system cost.
In fast PWM mode, the counter is incremented until the counter value matches the TOP value.
The counter is then cleared at the following timer clock cycle. The timing diagram for the fast
PWM mode is shown in
togram for illustrating the single-slope operation. The diagram includes non-inverted and
inverted PWM outputs. The small horizontal line marks on the TCNT0 slopes represent Com-
pare Matches between OCR0x and TCNT0.
clk_I/O
/2 when OCR0A is set to zero (0x00). The waveform frequency is defined by the following
Figure
11-8. The TCNT0 value is in the timing diagram shown as a his-
f
OCnx
=
--------------------------------------------------
2 N
⋅
⋅
(
f
clk_I/O
1
+
OCRnx
)
ATtiny25/45/85
OC0
75
=