Electronics > Projects, Designs, and Technical Stuff

DIY Modular Test Equipment Project

<< < (3/29) > >>

German_EE:
You would spend thousands of hours of work to complete this project. Is it really worth it?

Hell yeah! Why? Because it's FUN.

Rightnow I have a home made DC Power Supply, DC Dummy Load, 10 MHz Frequency Standard and RF Power Meter. On the ham bench there's also a home made DC Supply, home made Antenna Tuner and a home made transceiver that is a continuous work in progress. Only the scope, multimeter and VNA were made in a factory.

TiN:
Subbed.

I'd suggest 14-bit DAC for DC load. That will allow to set current in 1mA steps with some wiggle for calibration. Sometimes it's nice to have.
Or at least two ranges (low current, high current) like in some production DC loads. ;)

void_error:

--- Quote from: TiN on June 03, 2016, 01:50:00 am ---Subbed.

I'd suggest 14-bit DAC for DC load. That will allow to set current in 1mA steps with some wiggle for calibration. Sometimes it's nice to have.
Or at least two ranges (low current, high current) like in some production DC loads. ;)

--- End quote ---

Most likely going for the higher resolution DAC. 12-bit should do, that's 4096 steps and a suitable candidate is the DAC121C085. Same pinout as the DAC081C085, just more bits. Same 12-bit DAC will be used for the Lab Power Supply.

There's also a 10-bit variant, the DAC101C085.

spudboy488:

--- Quote from: void_error on June 02, 2016, 02:11:40 pm ---User Interface

Hardware:

* PIC16F18857 8-bit microcontroller, relatively new part but extremely versatile, this is the brain of the User Interface
* PIC16LF1455 8-bit USB microcontroller, used as an USB-UART interface
* MCP7940N Real time clock/calendar with battery backup, for optional data logging, hmm, I might even program the UI as an alarm clock

--- End quote ---

Look at the MCP2200 if all you're using the PIC16LF1455 for is a UART. IC plus 12 MHz resonator is all you need. No programming of the part required.[/list]

void_error:

--- Quote from: spudboy488 on June 03, 2016, 11:42:13 am ---Look at the MCP2200 if all you're using the PIC16LF1455 for is a UART. IC plus 12 MHz resonator is all you need. No programming of the part required.

--- End quote ---
I intend to keep the micro for USB-UART, offers more versatility which might come in handy later. Maybe I drag a friend of mine who's a programmer, to write the PC software to control things, he's pretty good with C#. That would mean programming the micro as a USB HID device, not too complicated since it's going to be based on one of Microchip USB examples / demos, porting the code from the 16(L)F1459 to the 1455 isn't too difficult as I've already ported USB stuff from the 16F45K50 (used in the microchip demo code) to the 25K50 and added my own stuff on top of it with o problems.

I probably haven't mentioned it before or at least not too clearly, but the User Interface board is also designed to be used as development board. For example, since it has both SPI and I2C it can be used to test code for different peripherals with the LCD providing debug data... and then there's the alarm clock :-DD. I'll actually program one for that sole purpose, just for fun, it already has buttons, a buzzer , RTCC and a display.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod