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  1. Z

    PIC controlled 907 clone

    I recently found this on ebay:http://www.ebay.com/itm/1PCS-Soldering-iron-handle-24V-50W-for-Soldering-iron-station-907A-852D-936-/232021180398?hash=item36058a3fee:g:bK8AAOSw0HVWBRRH and had a 12-0-12 transformer lying around. I had a look on the net and found a lot of Arduino PWM controlled...
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    Low Power 240V AC SMPS <30W flyback or forward?

    New attempt at flyback I have gone back to the books and slowly checked out what I was missing. I ended up designing a 12V 1A SMPS using UC3845 . Attached is the simetrix v8.0 file I simulated. Any feedback is welcome.
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    Thoughts on a diy multimeter

    DMM prototype V2 After considering complications simplicity always ends up winning. Attached is a simpler structure I am currently testing block by block it uses a single micro and will be battery powered. I am trying to hunt for 0.1% resistors on ebay + a reasonable current shunt. the opamps...
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    Thoughts on a diy multimeter

    I have been thinking of building an instrument lately based on the following: . Its still a thought at the time being. The 16F877A oversampling ADC in the diagram could be for testing purposes and get replaced with an ADS1115 or an LTC2400. Any feedback is welcome. Thanks
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    introduction to microcontrollers

    I have made a post at http://microcontrollerintro.blogspot.com/ for anyone to get a general idea of how to deal with microcontrollers in general and without being manufacturer specific. Its for novice only have a look your comments are welcome
  6. Z

    Low Power 240V AC SMPS <30W flyback or forward?

    Better results but still Hi am back after a long time and I wanted to get back to this project given that I got better cores to work with. I started with a simple DC flyback working from 18V to get 5V to get something simple working first and iron out all the issues. I can post more details if...
  7. Z

    DIY DAC + CD Player Project

    CS8416 bit clock not recovered Hi and merry xmas to everyone. In case anyone can help I have built a circuit board for the CS8416 and successfully obtained the Word select and Serial Data out of the CS8416.However my Bit clock signal (pin 27) is hanging at 3.3V. This is the schematic I am using...
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    LM324 Bench PSU

    Another schematic on the bench I have built the attached schematic and giving it a try. This one uses high side current sensing but the opamp used is temporary I am still thinking of whether to go with an ACS712 or MAX4080F. Any input is welcome. I have just received a STM32F103RBT6 board that...
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    Low Power 240V AC SMPS <30W flyback or forward?

    Found my issue After building a core quickly to reproduce the issues I was getting initially I finally found the culprit. Its the leakage inductance that was too high. Attached is a simulated VDS that looks exactly like my scope measurement I will rewind the transformer properly. In case this...
  10. Z

    Low Power 240V AC SMPS <30W flyback or forward?

    Simulation results this is the simulation result at 100KHz 0.5 DTC any feedback is welcome. the transformer is coiled I need to measure it and set its gap appropriately and the UC3845 controller is working fine. I will assemble the transformer on the board and keep posted. I am planning to run...
  11. Z

    Low Power 240V AC SMPS <30W flyback or forward?

    DCM flyback calculations I have attached my calculations if anyone can have a look and confirm its correct thanks.
  12. Z

    LM324 Bench PSU

    some update I have been able to get my code for rotary encoder user TIM4 and External interrupt for push button functions on a STM32VL discovery board, the same one I used when testing the analog part using ADC and DAC. Next step now is to assemble the code to have a digitally controlled PSU. I...
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    LM324 Bench PSU

    PSU schematic Attached is the psu I simulated, the simulation is for a full analog model based around X2. The potentiometers Vr1 and Vr2(they are not necessarily optimal here lower values should be used) will get replaced with the dac from the microcontroller as well as R25 and R26 to match the...
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    LM324 Bench PSU

    LM339 bench PSU Hi thanks for your input. Like i mentionned up i am using a modified schematic which i haven't yet posted. I see your point about TL431 and this is changed in the new schematic, i have effectively dropped voltage amplification in favour of a TL431 + Voltage follower. The current...
  15. Z

    LM324 Bench PSU

    TL494 Buck regulator prototype working Attached is a schematic of a voltage controlled buck regulator. I forgot to add the totem pole and gate drive resistor but at least it gives an idea of what I am heading for. This circuit will be used to drive the LM324 PSU and stay at full duty cycle all...
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    DC Electronic load another project to the list

    While testing an scoping the prototype of my LM723 i quickly designed a quick dc electronic load around a TL072 and an IRF540 and used it to test the PSU for light loading. Looking a little bit around an thinking a little bit long term i searched and bit an managed to extend the load to do...
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    PIC logic analyzer - digital storage oscilloscope

    16F628A schematics This is the unit I used to get the results I mentioned. In the meantime I will be trying the same approach with a STM32VL board and compare the results. Then i'll go back to solve my HM62256A stray noise issues.
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    PIC logic analyzer - digital storage oscilloscope

    Improvement with the real time analyzer I gave the 16F628A version another try. I have stopped sampling time and aimed only for the data. There seems to be a compromise to be made between buffer size, signal frequency and compiler operation mode. I am currently using a 80 bytes array to capture...
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    PIC logic analyzer - digital storage oscilloscope

    Working Logic analyzer Attached in a sample screen shot of the working logic analyzer software . For the time being the capture is done and sent to the pc @ 115200 Baud without any buffering. I am still working with the HM62256 RAM. I need to figure out why I am not getting the value I am...
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    PIC logic analyzer - digital storage oscilloscope

    Basic C# serial communication app I have successfully built a small C# application that receives the data being sent by the pic over a CP3102 serial to USB converter. Attached is a picture of the working app. There seems to be an issue with the disconnection which I need to fix otherwise it...
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