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  1. R

    Power Electronics for Beginners

    Thanks. Do you know of any others which are not too heavy in maths?
  2. R

    Power Electronics for Beginners

    Hi all, I am looking for some recommendations please. I am looking for a good book on power electronics for complete beginners. One that does not go to heavy into maths. I am looking for a change in career and getting into electronics for electric vehicles. I am a electronics technician but do...
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    SPI Signal Overshoot (to WIFI chip)

    No problem.
  4. R

    SPI Signal Overshoot (to WIFI chip)

    Yes they do
  5. R

    SPI Signal Overshoot (to WIFI chip)

    Sorry, yes SPI signal.
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    SPI Signal Overshoot (to WIFI chip)

    Hi, I have tried this. The square wave at probe comp looks fine, with no overshoot of the signal. I will try and upload a screenshot. The scope is a MSOX3024A KEYSIGHT. Thanks for your help
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    SPI Signal Overshoot (to WIFI chip)

    Hi I shortened the GND clip on the probe, it was set to x10. After this, the clock signal had no issues, however the mosi and miso still had overshoot/undershoot. The only thing that I can think of is inductance. I can add series damping resistors in each line, around 39R? Are there any other...
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    SPI Signal Overshoot (to WIFI chip)

    WFM2000 from SiLabs.
  9. R

    SPI Signal Overshoot (to WIFI chip)

    Hi all, I have been monitoring some SPI signals for a WiFi IC. The device is powered from 3.3V. The CLK frequency is 4.5MHz However, I am seeing overshoot and undershoot on the CLK, MISO etc For example on the CLK the overshoot can get to 3.9V. The undershoot is about -0.65V. This could cause...
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    Double functionality on Micro

    I have 2 backlights for a lcd and 1 extra led. Trying to connect from 2 i/o lines. Lcd have common anodes They all have to work independently.
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    Double functionality on Micro

    I have 2 buttons, the leds are already multiplexed. I think it may come down to using a shift register, this would mean trying to free up 3 i/o lines, clk, data and latch. Which i cant afford to do.
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    Double functionality on Micro

    Its a PIC16F1938..
  13. R

    Double functionality on Micro

    Hi The other pins are used for push buttons, LEDs, analogue inputs and buzzers.
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    Double functionality on Micro

    The 33K was used to stop the LED working when measuring current.. When it is a output it lights very briefly to flash every 1 minute. Would putting a diode in place of the 220R help? Or a zener diode? The only other thing i was thinking was to use a i/o expander as you mentioned. However i...
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    Double functionality on Micro

    Here is the schematic. any help would be appreciated.
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    Double functionality on Micro

    I wil upload a schematic too.
  17. R

    Double functionality on Micro

    Hi all, I have a issue where due to lack of i/o lines i need to double up on one i/o line. As an A/D to read light sensor and output to drive the LED. The light sensor output should go from 0 to 2.7V. However, it is being clamped to around 2V (forward volt drop of LED) i think it may be due to...
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    PIC A/D

    Is the 330K causing the issue as it increases the impedance. Or is the 330K x ADC leakage causing a voltage drop. Or should I reduce or remove the 2.2uF cap?
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    PIC A/D

    Hi, I have a 2.2uF cap and 330K resistor in parallel going into the A/D channel of the PIC at the emitter of a phototransistor.The Top part of the circuit is part of a light sensor. The PIC has a 10 bit A/D. However I am not seeing a full scale of 0V to 2.8V. Note. Using VDD (3.3V) as VREF for...
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    Pcb as antenna track

    Hi Many thanks for the information. I have a couple of more questions: 1. Please could you explain, what you mean by 'limited by the size of the PCB ground plane you are using'? 2. I am using the whole of layer 2 as a ground plane. What do I need to consider regarding this? 3. My thinking was...
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