AT90PWM3B-16SU Atmel, AT90PWM3B-16SU Datasheet - Page 262

• Manufacturer Part Number: AT90PWM3B-16SU
• Description: IC MCU AVR RISC 8K FLASH 32-SOIC
• Manufacturer: Atmel
• Series: AVR® 90PWM Lightingr

Specifications of AT90PWM3B-16SU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 27
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 11x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 32-SOIC (7.5mm Width)
• Processor Series: AT90PWMx
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: SPI/USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 27
• Number Of Timers: 2
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRFBKIT, ATAVRISP2
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 11-ch x 10-bit
• On-chip Dac: 1-chx10-bit
• Controller Family/series: AVR PWM
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 16MHz
• Rohs Compliant: Yes
• For Use With: ATSTK600-SOIC - STK600 SOCKET/ADAPTER FOR SOIC770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRMC200 - KIT EVAL FOR AT90PWM3 ASYNCATAVRFBKIT - KIT DEMO BALLAST FOR AT90PWM2ATAVRISP2 - PROGRAMMER AVR IN SYSTEMATSTK520 - ADAPTER KIT FOR 90PWM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

To work with the 10-bit DAC, two registers have to be updated. In order to avoid intermediate
value, the DAC input values which are really converted into analog signal are buffering into
unreachable registers. In normal mode, the update of the shadow register is done when the reg-
ister DACH is written.
In case DAATE bit is set, the DAC input values will be updated on the trigger event selected
through DATS bits.
In order to avoid wrong DAC input values, the update can only be done after having written
respectively DACL and DACH registers. It is possible to work on 8-bit configuration by only writ-
ing the DACH value. In this case, update is done each trigger event.
In case DAATE bit is cleared, the DAC is in an automatic update mode. Writing the DACH regis-
ter automatically update the DAC input values with the DACH and DACL register values.
It means that whatever is the configuration of the DAATE bit, changing the DACL register has no
effect on the DAC output until the DACH register has also been updated. So, to work with 10
bits, DACL must be written first before DACH. To work with 8-bit configuration, writing DACH
allows the update of the DAC.
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