Programing a C8051F380

[jesuscf]

We did note that if you overrange the ADC inputs on the F005, the chip dies.

Some ADCs from other micro-controller and ADC manufacturers (for example Atmel's AT89LP51RD2 & Microchip's MCP3008) have a voltage limiter built using two diodes and a series resistance connected to the analog inputs.  I have the impression that such protection circuit (or equivalent) may not be present in the Silabs' C8051F38x ICs.  I may be wrong though as the data sheet for the C8051F38x says the pins are 5V tolerant.  Perhaps it is time for some destructive tests...

[digsys]

  ... Perhaps it is time for some destructive tests...   

On similar spec MPUs in that series, I can vouch that they don't like 12V ! I've had ~5.5V on ADC pins on many occasions, without any
long/short term effects. either with Internal or external VRef. It was always one of those "oops" design testing moments :-)
The pdf says Max 5.8V for that part.

[ebclr]

For those ones, that don't know Silabs products, read the data sheet, and try to use before consider they antique or obsolete, In fact they are quite good, fast , flexible and cheap, and also extremely easy to use, with descent and cheap tools, and you can find anywhere debugger for this line ,for only USD 10 to flash and debug,  don't thing they are same as intel 8051 they aren't, they are old stuff made with new tech, have More mips that near all Pics and Atmels on same price level, with models with 24 bit ad converter on chip, also hardware multiply and division is a standard in all models, you can set any pin using the cross bar to do several functions, making the pcb work quite easy, very flexible power supply, and models with works for hours with a 1F capacitor as power supply, don't underestimate this best, They are the best options for small 8 bits systems . Try before criticize will worth the time.

[dannyf]

before consider they antique or obsolete

One has to have absolutely no idea about those chips to call them "antique" or "obsolete".

[jesuscf]

  ... Perhaps it is time for some destructive tests...   

On similar spec MPUs in that series, I can vouch that they don't like 12V ! I've had ~5.5V on ADC pins on many occasions, without any
long/short term effects. either with Internal or external VRef. It was always one of those "oops" design testing moments :-)
The pdf says Max 5.8V for that part.

C8051F38C pin with 1k ohm in series.  Applied 60Hz AC, 10V peak, from function generator (50 ohm output impedance).  Nothing bad happened as far as I can see.  The ADC works normally and within specs.

[mikerj]

  ... Perhaps it is time for some destructive tests...   

On similar spec MPUs in that series, I can vouch that they don't like 12V ! I've had ~5.5V on ADC pins on many occasions, without any
long/short term effects. either with Internal or external VRef. It was always one of those "oops" design testing moments :-)
The pdf says Max 5.8V for that part.

C8051F38C pin with 1k ohm in series.  Applied 60Hz AC, 10V peak, from function generator (50 ohm output impedance).  Nothing bad happened as far as I can see.  The ADC works normally and within specs.

You weren't actually applying 12v to the ADC in that case, the internal protection diodes would clamp the input voltage one Vf above Vdd and your external resistor limited the maximum current.

Certainly not good design practice.  It's using the device outside it's specifications and what can appear to work correctly initially can show up some very odd behavior later.  On some PICs is you forward bias the protection diodes on one of the the analog inputs, that channel can appear to work correctly whilst causing other channels to read incorrectly.

[Zoszko]

WoW I am impressed, I have not recieved any notifications on this topic.  But I am glad, I gave you something to talk about it.

As free_electron said:

you need to buy the silabs programming dongle. no way around it.

It's true, however buying the programmer did not solved it right away. I though my board is dead as the IDE said it cant identify the IC. I was trying everything except openin the bloody debug adapter. After 3 weeks I have ended up opening the little white box. Turns out they have f***** up the assembly (The 10pin connector was sitting on only one of the rows). QC pass sticker, srsly?

~Zoszko