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Ferrite cores in push-pull topology – Can anybody advise me on the choice of toroidal cores for an inverter above 3kva? If I combined two or more cores for more power delivery, how does it affect the calculations for windings? Read more
Need help with specifications for core base inverter transformer – I am trying to make an AC-DC inverter 12VDC to 220-240VAC (50Hz). It will be a center tapped transformer with two primary windings for switching purposes and one secondary winding. Read more
Power supply topology – I happened to come across this power supply schematic. I’m interested in knowing what will be the output. Read more
Low noise split supply converter – I want to go from +5V or +12V to +/-15V at 200mA. The noise/ripple must be very low because it is a supply for a low noise amp. The LT1533 has a nice demo board, but the push-pull transformer cannot be found and the Iout is a little low. Read more
400 V or 450 V electrolytic capacitor? – I am designing a 3 KW half bridge inverter for a 28 KHz output. The inverter will run on a single-phase, 220 VAC mains. I will use a 1200 uF electrolytic bypass capacitor for the DC-link. Should I use a 400 V or 450 V capacitor for nominal voltage?
Power supply voltage dip protection design – We have a system running in production and can’t avoid a power dip for some reason. When a power dip happens, one contactor (K1) trips. The contact part number is LP4K1210BW3. It has a 24 V DC triggered coil. We would like to design a power dip protection that will hold the K1 for three seconds when a power dip occurs. Read more
TRIAC for blocking high-frequency voltage – The figure here depicts a scenario in which two solid state switches are used and only one is ON at a time. The
problem is that the transformers are high-frequency transformers are running at 100KHz. Back-to-back MOSFETs could be used to implement the switches, but I am thinking of using TRIACs. How much improvement in dV/dt rating of the TRIAC can be expected with its gate is shorted to the anode terminal (by using MOSFET gate driver)? Read more
TRIAC is not switching off – Is there a need to have a resistor to ground from the gate of the TRIAC in the schematic below for more stability? Read more
Thyristor firing failed – I was practicing with a semicontrolled full wave rectifier. The load was a resitive one at first (100Ω)) and then changed to resistive-inductive load (100Ω) in series with 200 mH). I had no problem with the resistive load but I do with the RL load. The firing circuit and the complete schematic is below. Read more
Negative output in SMPS – I am having some confusion with this diagram. I am having doubt in this 3 unit. In the first 2, I need -85 V and -93 V respectively. Where in 3rd, I need -12 V. Is the arrangement of the components here correct or not? Read more
