AT32UC3L0256 Atmel Corporation, AT32UC3L0256 Datasheet - Page 667

• Manufacturer Part Number: AT32UC3L0256
• Manufacturer: Atmel Corporation

Specifications of AT32UC3L0256

• Flash (kbytes): 256 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 Speed: No
• Usb Interface: No
• Spi: 5
• Twi (i2c): 2
• Uart: 4
• Lin: 4
• 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

28.5.6
28.5.7
28.6
28.6.1
32145A–12/2011
Functional Description
Analog Comparators
Debug Operation
Acquisition Types
(MBLEN) when using the QMatrix acquisition method. Two additional handshakes support DMA-
Touch by regulating transfers from memory to the DMATouch State Write Register (DMATSW)
and from the DMATouch State Read Register (DMATSR) to memory. The Peripheral DMA Con-
troller must be configured properly and enabled in order to perform direct memory access
transfers to/from the CAT module.
When the CAT module is performing QMatrix acquisition, it requires that on-chip analog compar-
ators be used as part of the process. These analog comparators are not controlled directly by
the CAT module, but by a separate Analog Comparator (AC) Interface. This interface must be
configured properly and enabled before the CAT module is used. This includes configuring the
generic clock input for the analog comparators to the proper sampling frequency.
The CAT will automatically use the negative peripheral events from the AC Interface on every Y
pin in QMatrix mode. When QMatrix acquisition is used the analog comparator corresponding to
the selected Y pins must be enabled and converting continuously, using the Y pin as the positive
reference and the ACREFN as negative reference.
When an external debugger forces the CPU into debug mode, the CAT continues normal opera-
tion. If the CAT is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
The CAT module can perform several types of QTouch acquisition from capacitive touch sen-
sors: autonomous QTouch (one sensor only), DMATouch, QTouch group A, and QTouch group
B. The CAT module can also perform QMatrix acquisition. Each type of acquisition has an asso-
ciated set of pin selection and configuration registers that allow a large degree of flexibility.
The following schematic diagrams show typical hardware connections for QTouch and QMatrix
sensors, respectively:
Figure 28-2. CAT Touch Connections
AVR32 Chip
SNSKn
SNSn
Cs (Sense Capacitor)
AT32UC3L0128/256
QTouch
Sensor
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