microcontroller oscilloscope

[yalect]

Hello,
I am looking for simple usb oscilloscope project based on microcontroller maybe Atmel it's better but working with high frequency above 25Mhz
may you have ideas?
thank you

[Fungus]

... simple ... above 25Mhz

That's a contradiction.

based on microcontroller maybe Atmel

Arduinos only run at 16Mhz and they take many clock cycles to read the ADC.

[promacjoe]

Arduino DUE runs at 84Mhz, on a 32-bit ARM core microcontroller.

[Fungus]

Arduino DUE runs at 84Mhz, on a 32-bit ARM core microcontroller.

I know that...    But he said "Atmel microcontroller", not "ARM processor" so I'm guessing that's not what he was thinking of.

[nbritton]

This is a fool's errand if your goal is to get a functional oscilloscope. You would be much better off buying something pre-made like the Analog Discovery which is capable of 45 MHz bandwidth and has differential inputs, get yourself an academic email address and you can pick this up for $159. Alternatively there is also the Red Pitaya.

It says in the datasheet that the Atmel XMega microcontroller's ADC only has the throughput for 4 MSa/s: http://www.atmel.com/products/microcontrollers/avr/AVR_XMEGA.aspx

[promacjoe]

Arduino DUE runs at 84Mhz, on a 32-bit ARM core microcontroller.

I know that...    But he said "Atmel microcontroller", not "ARM processor" so I'm guessing that's not what he was thinking of.

I thought it Included all Arduino+Atmel products.
The Arduino Due is a microcontroller board based that uses the Atmel SAM3X8E ARM Cortex-M3 CPU.

otherwise I would've included the pcDuino3, it is a 1GHz ARM Cortex A7 Dual Core. But it is not an Arduino product. Only Arduino compatible.

[Fungus]

This is a fool's errand

...unless your only goal is to learn about "making ascilloscopes".

You would be much better off buying something pre-made like the Analog Discovery which is capable of 45 MHz bandwidth

No it isn't. It's more like 10 MHz.

[Fungus]

I thought it Included all Arduino+Atmel products.

You never know    I was just guessing based on the tone of the post.

It's not going to makee a 25MHz 'scope either way.

[Fungus]

With the BNC adapter board its measured 3db BW is 25MHz or greater.

OK, didn't know that. 

It's quite a fun/useful device if you can get the discount.

[Zero999]

This is a fool's errand if your goal is to get a functional oscilloscope. You would be much better off buying something pre-made like the Analog Discovery which is capable of 45 MHz bandwidth and has differential inputs, get yourself an academic email address and you can pick this up for $159. Alternatively there is also the Red Pitaya.

It says in the datasheet that the Atmel XMega microcontroller's ADC only has the throughput for 4 MSa/s: http://www.atmel.com/products/microcontrollers/avr/AVR_XMEGA.aspx

I agree but you definitely need the discount, otherwise you're better off with an entry level Chinese 'scope such as something from UNI-T, Hantek, Owon Rigol etc.