Search:

Type: Posts; User: KlausST

Page 1 of 20 1 2 3 4

Search: Search took 0.11 seconds.

  1. Closed: Re: White residue after solder mask develope!!!

    Hi,


    I have to agree.

    I see a bright - almost white part at the hole --- I think this just is the reflection of the light.

    Klaus
  2. Replies
    5
    Views
    202

    Closed: Re: Coupled inductors for filtering

    Hi,

    Generally there are (at least) two types of inductors:
    * EMI / EMC filtering inductors. Low Q for damping unwanted frequencies. Often high inductance.
    * power inductors, high Q for low loss....
  3. Replies
    6
    Views
    241

    Closed: Re: IR2130 problems in Proteus

    Hi,

    Why the zeners across GS?
    The drive voltage is 15Vmax and the Mosfets can widthstand 20V.
    I see no reason for the zeners ... also zeners often suffer from high capacitance.

    V_SO is the...
  4. Replies
    6
    Views
    241

    Closed: Re: IR2130 problems in Proteus

    Hi,

    I can't open a .rar file on my tablet...

    Klaus
  5. Replies
    5
    Views
    202

    Closed: Re: Coupled inductors for filtering

    Hi,

    a common mode choke may be very high impedance for common mode signals, but it may be very low impedance for differential mode signals.
    You can get the same when you use two not coupled...
  6. Closed: Re: What is default slave address for the ACS71020

    Hi,


    Thanks a lot for this ...

    But first you need to give all your informations: (for sure also - as soon as possible ;-))
    * complete schematic of all around the metering IC( power, power...
  7. Replies
    10
    Views
    419

    Closed: Re: What's the rpoblem of this MIC circuits?

    Hi,


    With "input" I meant the signal in your circuit that is marked "Vin".
    And yes it goes to the inverting input of the amp.

    Note: In your circuit of post#9 there also is a 10k series...
  8. Closed: Re: White residue after solder mask develope!!!

    Hi,

    What exactly do you mean?

    Add some marks on the pictures.

    Klaus
  9. Replies
    8
    Views
    359

    Closed: Re: Coaxial cable capacitance

    Hi,

    Yes you miss the characteristic impedance.

    You just need to drive the 75 Ohms of the cable impedance, that's it. This already includes the cable capacitance.
    And it's independent of cable...
  10. Replies
    10
    Views
    468

    [SOLVED]Closed: Re: Transformers on a PCB

    Hi,


    No!

    Repeated:


    Klaus
  11. Replies
    4
    Views
    259

    [SOLVED]Closed: Re: how to calculate ib of PNP

    Hi


    you missed the brackets:
    ((5V7-V_in-v_d1)*R2/(R1+R2))/R2
    then you may simplify it:
    --> ((5V7-V_in-v_d1)*R2/(R1+R2))/R2
    --> (5V7-V_in-v_d1)/(R1+R2)
    (simple Ohm´s law: I = V / R)
  12. Replies
    10
    Views
    468

    [SOLVED]Closed: Re: Transformers on a PCB

    Hi,

    We are talking about HF. Thus this still is far away from being a GND plane.
    All the traces have the same length as before ... and for HF the width doesn´t play much a role.

    Simple...
  13. Replies
    4
    Views
    259

    [SOLVED]Closed: Re: how to calculate ib of PNP

    Hi,

    hard to say without values. I guess 300 uA.

    No - joke aside.

    do you really want us to go give you a mathematical solution for all cases you can think of?
    * DC, what range?
    * AC, what...
  14. Replies
    10
    Views
    468

    [SOLVED]Closed: Re: Transformers on a PCB

    Hi,

    It does not depend on whether your circuit produces HF or not, it depends whether your circuit reacts on HF. And this depends on what exactly U1 is.

    In either case: In times of many HF...
  15. Replies
    7
    Views
    349

    Closed: Re: Soldering Iron recommendations

    Hi,

    we have more modern ones like JBC for example, but I can see no benefit against the "old ones".
    They claim about longer tip liefetime - but we see the opposite.
    And no, we don´t need to...
  16. Closed: Re: 0-100uA analogue meter (needle) to show 0-10v

    Hi,

    according ohm´s law. 5V input will give 50uA, this is half of 100uA.
    So this should be linear.

    Nobody can tell whether your meter works linearely or not. How? You don´t give any...
  17. Replies
    7
    Views
    349

    Closed: Re: Soldering Iron recommendations

    Hi,


    In our company we design multilayer PCB, do prototype soldering, rework, repair, low volume production.
    In our whole company we only have soldering stations up to 50W.

    Mainly we use...
  18. Closed: Re: PROCESSOR IS REBOOTING when hotplugging usb console to processor's Board through

    Hi,


    I didn't talk about "onboard" either...

    Before you just talked about a laptop and FTDI....but now I have to assume it's not the laptop that is rebooting.
    You know ... any laptop has a...
  19. Closed: Re: PROCESSOR IS REBOOTING when hotplugging usb console to processor's Board through

    Hi,

    You talk about RS232 signal lines.

    But I think the signal lines do not cause the problem.
    I'm even not sure if it's a hardware problem at all.
    It may be a software problem:
    * OS, FTDI...
  20. Closed: Re: [PIC] Car Cooling System PSU Design Related

    Hi,

    There are still a lot if issues..already discussed.

    A new one is Q5.
    What does it do? It disconnects GND to U1 in a live system. GND is it's reference...most voltages specified in the...
  21. Replies
    3
    Views
    240

    Closed: Re: Simple ADC code in XC8 for PIC16F18856

    Hi,


    Do the timings really make sense?
    * discharging C_Hold typicaly takes a microsecond or so, discharging it for 250us won't do anything..
    * sampling time is also in the range of...
  22. Replies
    10
    Views
    419

    Closed: Re: What's the rpoblem of this MIC circuits?

    Hi,

    A2 has a defined gain of -1, thus it should work.

    A1 has an input impedance of 1600 Ohms @ 1kHz (C7). This causes a gain of -32 @ 1kHz. But there is a good chance that it oscillates ......
  23. Replies
    10
    Views
    419

    Closed: Re: What's the rpoblem of this MIC circuits?

    Hi,

    I think the circuit could work.

    But why do you use a pulse input ... of that high magnitude.?
    --> Use a sine shape waveform of 1kHz and 30mV amplitude.

    The circuit as is amplifies high...
  24. Closed: Re: [PIC] Car Cooling System PSU Design Related

    Hi,

    Why not simply switching low side = GND of the peltier?
    Why not using a dedicated Highside_switch?
    Why not using standard P_channel circuits to control high side?

    Klaus
  25. Closed: Re: Supercap charging using load switch and current limit resistor

    Hi,


    Yes. Turn ON starts at about 1.8V, but one can not see this, becayse the signal is chip internal. But after the turn ON delay you see the output.


    As always: (true for any resistive...
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4