ATTINY44-15MZ Atmel, ATTINY44-15MZ Datasheet - Page 107

• Manufacturer Part Number: ATTINY44-15MZ
• Description: MCU AVR 4K FLASH 15MHZ 20-QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY44-15MZ

• Package / Case: 20-QFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 12
• Eeprom Size: 256 x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Program Memory Size: 4KB (4K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: USI
• Core Size: 8-Bit
• Processor Series: ATTINY4x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: SPI, UART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

14.9.4
7701E–AVR–02/11
Phase Correct PWM Mode
The phase correct pulse width modulation, or phase correct PWM, mode (WGM13:0 = 1, 2, 3,
10, or 11) provides a high-resolution phase correct PWM waveform generation option. The
phase correct PWM mode is, like the phase and frequency correct PWM mode, based on a
dual-slope operation. The counter counts repeatedly from bottom (0x0000) to top and then
from top to bottom.
In non-inverting compare output mode, the output compare (OC1x) is cleared on the compare
match between TCNT1 and OCR1x while up-counting, and set on the compare match while
down-counting. In inverting output compare mode, the operation is inverted. The dual-slope
operation has lower maximum operation frequency than single-slope operation. However, due
to the symmetric feature of the dual-slope PWM modes, these modes are preferred for motor
control applications.
The PWM resolution for the phase correct PWM mode can be fixed to 8, 9, or 10 bits, or
defined by either ICR1 or OCR1A. The minimum resolution allowed is 2 bits (ICR1 or OCR1A
set to 0x0003), and the maximum resolution is 16 bits (ICR1 or OCR1A set to max). The PWM
resolution in bits can be calculated by using the following equation:
In phase correct PWM mode, the counter is incremented until the counter value matches
either one of the fixed values 0x00FF, 0x01FF, or 0x03FF (WGM13:0 = 1, 2, or 3), the value in
ICR1 (WGM13:0 = 10), or the value in OCR1A (WGM13:0 = 11). The counter has then
reached the top, and changes the count direction. The TCNT1 value will be equal to top for
one timer clock cycle. The timing diagram for the phase correct PWM mode is shown on
ure 14-8 on page
used to define top. The TCNT1 value in the timing diagram is shown as a histogram for illus-
trating the dual-slope operation. The diagram includes non-inverted and inverted PWM
outputs. The small horizontal lines on the TCNT1 slopes represent compare matches between
OCR1x and TCNT1. The OC1x interrupt flag will be set when a compare match occurs.
Figure 14-8. Phase Correct PWM Mode, Timing Diagram
TCNTn
OCnx
OCnx
Period
107. The figure shows phase correct PWM mode when OCR1A or ICR1 is
Atmel ATtiny24/44/84 [Preliminary]
1
R
PCPWM
2
=
log
---------------------------------- -
log
TOP
3
2
+
1
4
OCRnx/TOP Update and
OCnA Interrupt Flag Set
or ICFn Interrupt Flag Set
(Interrupt on TOP)
TOVn Interrupt Flag Set
(Interrupt on Bottom)
(COMnx1:0 = 2)
(COMnx1:0 = 3)
Fig-
107