AT43312A-SC SL383 Atmel, AT43312A-SC SL383 Datasheet - Page 12

• Manufacturer Part Number: AT43312A-SC SL383
• Manufacturer: Atmel

Specifications of AT43312A-SC SL383

• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Package Type: SOIC
• Mounting: Surface Mount
• Pin Count: 32
• Lead Free Status / RoHS Status: Not Compliant

Power Supply
The AT43312A is powered from the USB bus, but has an internal voltage regulator to
supply the 3.3V operating power to its circuitry. For proper operation, an external high
quality, low ESR, 0.27 µF or larger, capacitor should be connected to the output of the
regulator, CEXT pin and ground. The CEXT pin can also be used to supply the voltage
to the 1.5K pull-up resistor at Port 0’s DP pin.
To provide the best operating condition for the AT43312A, careful consideration of the
power supply connections are recommended. Use short, low impedance connections to
both power supply lines: VCC and VSS. Use sufficient decoupling capacitance to
reduce noise: 0.1 µF of high quality ceramic capacitor soldered as close as possible to
the VCC and VSS package pins. Package pins are recommended.
The AT43312A can also operate directly off a 3.3V power supply. In this case, leave the
VCC pin floating and connect the 3.3V power to the CEXT pin.
AT43312A
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1255G–USB–05/06