Chameleon-AVR Nurve Networks, Chameleon-AVR Datasheet - Page 29

• Manufacturer Part Number: Chameleon-AVR
• Description: MCU, MPU & DSP Development Tools AVR8 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-AVR

• Processor To Be Evaluated: AVR 328P
• Data Bus Width: 8 bit
• Interface Type: USB, VGA, PS/2, I2C, ISP, SPI
• Operating Supply Voltage: 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

© 2009 NURVE NETWORKS LLC “Exploring the Chameleon AVR 8-Bit”
2.0 5.0V & 3.3V Power Supplies
Figure 2.1 – The Chameleon AVR power supply design.
The Chameleon AVR system has a duel 3.3V / 5.0V power supply system that is feed by a single 9V DC unregulated
input from a wall adapter or feeds from the USB port header. The supplies design is shown in Figure 3.1 for reference.
The supplies are straight forward, the only interesting thing is the coupling of the USB power and the regulated power at
node 1 of the power switch SW1. This allows the system to use power from either the regulated supply or the USB port.
The Chameleon AVR is a mixed voltage system to support 5V AVR and 3.3V Propeller chip. Both supplies are
independent and can each supply up to 500 mA for all your needs. Additionally, the power supplies are exported to the
expansion header J7 for external interfacing.
3.0 Reset Circuit
Figure 3.1 – The Chameleon AVR reset circuit.
The Chameleon AVR can be reset externally via a number of sources including the reset switch SW2, the ISP
programming port as well as pressing as thru the DTR or RTS lines of the USB UART. The reset circuitry on the AVR
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