Amicus18/Arduino/Whatever voltages

[dhouston]

In designing the shields I want to be sure the correct voltage is supplied to the modules. The ConnectOne modules use 3V3 and are not 5V tolerant. The Tibbo is 3.3V but its input pins are 5V tolerant. I'm not sure about the GA1000 but it only connects to the EM500 and to the save 3V3 source. The flash chip is 3V3 and also only connects to the EM500. I need to make sure that they not only have a 3V3 supply but that the supply is also capable of the rather high currents drawn by the WiFi modules when transmitting (250-350mA).

The problem is that with the proliferation of compatibles, there seems to be a plethora of power schemes. For example, the Arduino Duemilanove (and compatibles) automatically switches between USB power and an external source (if one is plugged in) but I'm not at all certain what will be on the 5V, 3V3 & Vin pins under various scenarios. The 3V3 supply on this model is taken from USB which can only supply 50mA. I have no idea what Vin equals if the external supply is 3V3.

Any suggestions from all of the shield experts here?

[Gevo]

Hello Dave,

Here you have a point of discussion. The Arduino is a 5-volt based Atmel. The Amicus18 (PIC18F25K20) 3V3. But, the free Proton Compiler is also support (version 1.0.1.6) the PIC18F25K22 (5-volt device). I have design a clone of the Amicus18 board. The Ami18 Board, with a other power scheme and USB mini. Input power can be USB, external DC_IN or via ICSP™. (Microchip PICKit™ 2 and PICKit™) I use the board with the 3V3 and 5-volt PICs and some shields and this works very well. The 3V3 low-drop regulator LD1117 is current up to 800mA. Drive a WiFi is no problem. For programming I use PBP V2.60C

Ami18 Board schematic. AMI18 BOARD schematic Rev 1.0.pdf

[dhouston]

The Arduino is a 5-volt based Atmel. The Amicus18 (PIC18F25K20) 3V3. But, the free Proton Compiler is also support (version 1.0.1.6) the PIC18F25K22 (5-volt device). I have design a clone of the Amicus18 board. The Ami18 Board, with a other power scheme and USB mini. Input power can be USB, external DC_IN or via ICSP™. (Microchip PICKit™ 2 and PICKit™) I use the board with the 3V3 and 5-volt PICs and some shields and this works very well. The 3V3 low-drop regulator LD1117 is current up to 800mA. Drive a WiFi is no problem. For programming I use PBP V2.60C

Yes - I learned that the official Arduinos are 5V only after starting this thread. I did find a web page with instructions for converting one to 3V3.

Is the Ami18 available? The link you provided appears broken.

I had earlier started a discussion in ZBasic's forums about designing my own clone with power supplied by an external 3V3 or 5V AMPS. These are available in 1.5A or more capacity. That discussion was turned towards converting an existing board to run ZBasic chips (which require a crystal change with the crystal depending on whether it uses 3V3 or 5V) and it was while exploring that option that I learned of the 5V only issue. I guess I was late to the party.

There is a Xino basic kit for Atmel.

[Gevo]

Hello Dave,

I know the Xino Atmel of Ciseco in the UK. But, we a Authorized Microchip Design Partner, so we stay by the PICmicro's :-) And I can tell you, there is a lot news in the World of the PICs... Android Shields to controll your application (robotics) by cell phones, the Uno32 and Max32 based on Arduino but with the PIC32xx.

Some things we test and make, see www.picshop.nl

Oh, I use for up to 10 years PBP, so this is for us the best choice in BASIC.

Regards,
Gevo