AT90USB162 Atmel Corporation, AT90USB162 Datasheet - Page 44

• Manufacturer Part Number: AT90USB162
• Manufacturer: Atmel Corporation

Specifications of AT90USB162

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 22
• Ext Interrupts: 21
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• 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: 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
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

8.6.2
8.7
8.7.1
44
Minimizing Power Consumption
AT90USB82/162
Power Reduction Register 1 - PRR1
Analog Comparator
• Bit 4 - Res: Reserved bit
This bit is reserved and will always read as zero.
• Bit 3 - PRTIM1: Power Reduction Timer/Counter1
Writing a logic one to this bit shuts down the Timer/Counter1 module. When the Timer/Counter1
is enabled, operation will continue like before the shutdown.
• Bit 2 - PRSPI: Power Reduction Serial Peripheral Interface
Writing a logic one to this bit shuts down the Serial Peripheral Interface by stopping the clock to
the module. When waking up the SPI again, the SPI should be re initialized to ensure proper
operation.
• Bit 1 - Res: Reserved bit
These bits are reserved and will always read as zero.
• Bit 0 - Res: Reserved bit
These bits are reserved and will always read as zero.
• Bit 7 - PRUSB: Power Reduction USB
Writing a logic one to this bit shuts down the USB by stopping the clock to the module. When
waking up the USB again, the USB should be re initialized to ensure proper operation.
• Bit 6..1 - Res: Reserved bits
These bits are reserved and will always read as zero.
• Bit 0 - PRUSART1: Power Reduction USART1
Writing a logic one to this bit shuts down the USART1 by stopping the clock to the module.
When waking up the USART1 again, the USART1 should be re initialized to ensure proper
operation.
There are several issues to consider when trying to minimize the power consumption in an AVR
controlled system. In general, sleep modes should be used as much as possible, and the sleep
mode should be selected so that as few as possible of the device’s functions are operating. All
functions not needed should be disabled. In particular, the following modules may need special
consideration when trying to achieve the lowest possible power consumption.
When entering Idle mode, the Analog Comparator should be disabled if not used. In other sleep
modes, the Analog Comparator is automatically disabled. However, if the Analog Comparator is
set up to use the Internal Voltage Reference as input, the Analog Comparator should be dis-
abled in all sleep modes. Otherwise, the Internal Voltage Reference will be enabled,
Bit
Read/Write
Initial Value
7
PRUSB
R/W
0
6
–
0
R
5
–
R
0
4
–
R
0
3
-
R/W
0
2
–
R
0
1
–
R
0
0
PRUSART1
R/W
0
7707F–AVR–11/10
PRR1