SAM3U2E Atmel Corporation, SAM3U2E Datasheet - Page 1126

• Manufacturer Part Number: SAM3U2E
• Manufacturer: Atmel Corporation

Specifications of SAM3U2E

• Flash (kbytes): 128 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 96 MHz
• Cpu: Cortex-M3
• # Of Touch Channels: 57
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 1
• Quadrature Decoder Channels: 1
• Usb Speed: Hi-Speed
• Usb Interface: Device
• Spi: 5
• Twi (i2c): 2
• Uart: 5
• Ssc: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 12
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 36
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: No
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.62 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

43.4.9
43.4.9.1
43.4.9.2
1126
SAM3U Series
Crystal Oscillators Design Consideration Information
Choosing a Crystal
Printed Circuit Board (PCB)
When choosing a crystal for the 32768 Hz Slow Clock Oscillator or for the 3-20 MHz Oscillator,
several parameters must be taken into account. Important parameters between crystal and
SAM3U specifications are as follows:
SAM3U Oscillators are low power oscillators requiring particular attention when designing PCB
systems. A board design example is given on Atmel’s website in the MCU Technical Center
Section.
• Load Capacitance
• Drive Level
• Equivalent Series Resistor (ESR)
• Shunt Capacitance
– This is the equivalent capacitor value the oscillator must “show” to the crystal in
– Crystal drive level >= Oscillator Drive Level. Having a crystal drive level number
– Crystal ESR <= Oscillator ESR Max. Having a crystal with ESR value higher than
– Max. crystal Shunt capacitance <= Oscillator Shunt Capacitance (
order to oscillate at the target frequency. Crystal must be chosen according to the
internal load capacitance (C
load capacitance will result in a frequency drift.
lower than the oscillator specification may damage the crystal.
the oscillator may cause the oscillator to not start.
Having a crystal with ESR value higher than the oscillator may cause the
oscillator to not start.
L
)of the on-chip oscillator. Having a mismatch for the
6430E–ATARM–29-Aug-11
C
SHUNT
).