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Recent content by Fluorescence

  1. Fluorescence

    Non compensated SMPS works fine

    i'm afraid i don't know why they work, also, i don't know if they will suffer in a noisy environment due to the lack of loop compensation.
  2. Fluorescence

    Electronic design

    thanks for all this great advice! I cannot afford to patent it or anything, and i can't afford to set up myself, so i will be very happy to work as a designer to do these products just like any designer in any other company. By the way, these are mains domestic LED lighting products, specially...
  3. Fluorescence

    Power factor of mains diode bridge

    Hello "Just to be clear: the "reflected" power concept is completely wrong. " ....the thing is, if you please see the following article.. http://www.scribd.com/doc/7694921/On-Switch-Mode-Power-Supply-Reference-Manual ..please see page 32, left-hand-side, 2nd paragraph down.. -It clearly...
  4. Fluorescence

    Boost converter transfer function

    Hello, I have designed a boost converter with the following specification Vin = 24V Vout = 40V Output power = 10W Switching frequency = 100KHz Continuous conduction mode Output caps = 400uF Output caps ESR = 0.33R Boost inductor = 1mH Ripple current = 10% PWM controller = LT1241 Current mode...
  5. Fluorescence

    Non compensated SMPS works fine

    thankyou Zappedagain, Actually , i am wondering now if my uncompensated circuit is maybe OK. the HV9910B uses this uncompensated control and must be OK, i guess... http://www.supertex.com/pdf/datasheets/HV9910B.pdf also, the IRS2541 uses this type of control and must also be OK, agin...
  6. Fluorescence

    Non compensated SMPS works fine

    Hello, A circuit that doesn’t work is not nice, but a circuit that does work when it shouldn’t is even worse!………. I am designing mains LED lighting and am using UC3842 PWM controller since it costs just 20 Cents. (Specific LED drivers are too expensive) I have designed two similar current...
  7. Fluorescence

    Slope compensation for current mode SMPS

    You can use slope compensation in a current mode led driver see http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1094,C1766,P81080,D26364 it also has a Vc pin for loop compensation.
  8. Fluorescence

    Minimum voltage level required or Powering CFL's

    Thanks VE1BLL, i am now searching for latest literature on the lowest possible working voltage of a CFL though it does not seem to be available on the web.
  9. Fluorescence

    Minimum voltage level required or Powering CFL's

    Hello, I am writing concerning powering CFLs (Compact Fluorescent Lamps) from the mains. The following App Note from IRF.com shows a fluorescent lamp being powered from the UK mains (240V) .... ...but uses a "valley filler" passive power factor corrector, so the DC bus actually varies from...
  10. Fluorescence

    SMPS stability

    Thankyou xnuke.. "I see iterative trial and error, and no satisfactory measure of a margin to instability is proposed." ..the supporters of this time domain analysis would say that they would get sufficient phase margin by changing compensation components until an optimised transient response...
  11. Fluorescence

    SMPS stability

    Sorry i forgot to add the background to this post... A few years ago i was at an interview at a branch of a large and well known switcher company and the Engineering Manager (who i notice often contributes technical articles to power electronic periodicals) said that no matter how many...
  12. Fluorescence

    SMPS stability

    hello, With these fora having recently debunked myths concerning 1. Power factor correction and efficiency 2. Right half plane zero of boost converter ...i wonder if the situation concerning ensuring the stability of a switcher power supply using time domain (step response) methods only is...
  13. Fluorescence

    Formula for Right Half Plane Zero in a Boost Converter

    Hello, Sorry if i've missed something here, but Equation 13 (page 21) of the following "Control Loop Cookbook" by Lloyd Dixon http://focus.ti.com/lit/ml/slup113a/slup113a.pdf gives the Boost's and Flyback's RHPZ as having a D in the denominator. Sorry to drag this up again, but can we now...
  14. Fluorescence

    Feedback compensation on flyback PFC

    Hello, I write concerning a flyback PFC stage with L6561. I refer to Figure 16, page 18 of the following app note... http://www.st.com/stonline/products/literature/an/5956.pdf There are feedback compensation components on both primary and secondary sides. Is this unusual? I would have...
  15. Fluorescence

    Formula for Right Half Plane Zero in a Boost Converter

    Thankyou very much, soryy if this was hijacking the post away from OP.

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