ATUC64L4U Atmel Corporation, ATUC64L4U Datasheet - Page 39

• Manufacturer Part Number: ATUC64L4U
• Manufacturer: Atmel Corporation

Specifications of ATUC64L4U

• Flash (kbytes): 64 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 50 MHz
• Cpu: 32-bit AVR
• # Of Touch Channels: 17
• Hardware Qtouch Acquisition: Yes
• Max I/o Pins: 36
• Ext Interrupts: 36
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 2
• Uart: 4
• Lin: 4
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 12
• Adc Speed (ksps): 460
• Analog Comparators: 8
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 16
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.62 to 3.6
• Operating Voltage (vcc): 1.62 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 6
• Output Compare Channels: 18
• Input Capture Channels: 12
• Pwm Channels: 35
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

6. Supply and Startup Considerations
6.1
6.1.1
6.1.2
32142A–12/2011
Supply Considerations
Power Supplies
Voltage Regulator
The ATUC64/128/256L3/4U has several types of power supply pins:
The ground pins GND are common to VDDCORE, VDDIO, and VDDIN. The ground pin for
VDDANA is GNDANA.
When VDDCORE is not connected to VDDIN, the VDDIN voltage must be higher than 1.98V.
Refer to
For decoupling recommendations for the different power supplies, please refer to the schematic
checklist.
Refer to
The ATUC64/128/256L3/4U embeds a voltage regulator that converts from 3.3 V nominal to
1.8V with a load of up to 60 mA. The regulator supplies the output voltage on VDDCORE. The
regulator may only be used to drive internal circuitry in the device. VDDCORE should be exter-
nally connected to the 1.8V domains. See
Adequate output supply decoupling is mandatory for VDDCORE to reduce ripple and avoid
oscillations. The best way to achieve this is to use two capacitors in parallel between VDDCORE
and GND as close to the device as possible. Please refer to
decoupling capacitors values and regulator characteristics.
Figure 6-1.
The voltage regulator can be turned off in the shutdown mode to power down the core logic and
keep a small part of the system powered in order to reduce power consumption. To enter this
mode the 3.3V supply mode, with 1.8V regulated I/O lines power supply configuration must be
used.
3.3V
1.8V
• VDDIO: Powers I/O lines. Voltage is 1.8 to 3.3V nominal.
• VDDIN: Powers I/O lines, the USB pins, and the internal regulator. Voltage is 1.8 to 3.3V
• VDDANA: Powers the ADC. Voltage is 1.8V nominal.
• VDDCORE: Powers the core, memories, and peripherals. Voltage is 1.8V nominal.
nominal if USB is not used, and 3.3V nominal when USB is used.
Section 35. on page 895
Section on page 10
Supply Decoupling.
C
IN3
for power supply connections for I/O pins.
C
C
for power consumption on the various supply pins.
OUT2
IN2
Section 6.1.3
C
C
OUT1
IN1
ATUC64/128/256L3/4U
for regulator connection figures.
VDDCORE
VDDIN
Section 35.8 on page 908
Regulator
1.8V
for
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