Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
The application circuit in the data sheet seems to simulate well on 6 V with a high-value load resistance. It will go into a burst-mode of operation at light loads as shown.
You should use the recommended online app WEBENCH to test, tweak and finalize from your initial design values.
The software sometimes will complain about floating nodes and convergence, so I usually place large resistances referenced to the circuit GND. You can place fixed probes or probe a device pin or current in wire, etc. You obviously have to set up your transient simulation parameters first.
Be...
Your control loop may not have enough gain to deal with the resonant bump from the output filter. If you have a 1000 uF/400V electrolytic available, try to add that with a 2.2 ohm in series over the output to see if this additional damping helps with the problem. I messed around with the gain of...
It is usually only a problem that comes up with indirect transfer converters, like boost, buck-boost and flyback. Operating deep into CCM will make the problem worse, and as stated the crossover must be reduced very low to avoid the RHP zero effects.
Well, we can substitute from an external power supply the voltage that the bias supply would normally supply, and measure if there are any activity around the PFC/switching chip once we can look up the chip data. This can be done without applying mains to the PSU itself. We might be able to...
Make sure your standby/bias supply is working. This is using the TNY280 chip. Without this giving the correct power, the rest of the circuits may not start up correctly. Also identify the PFC/switcher controller chip/s. You want to check the two clamping diodes connected to the MOSFET's that I...
Here is another circuit (like we don't have enough already), which seems happy operating with either an MOSFET or BJT. It shows no stability problems from simulation results and phase margin stays above 50 deg for a 500 ohm lower (not including the 250 ohm sense resistor) loop resistance and...
Yep, similar frustrations this side. The best stable version was 10, before they added a lot of new features. Often it will plot graphs on top of each other with no way to separate them. Then when collecting and messing with it, it will crash with illegal operation. Sometimes with an AC sweep it...
Nice circuit! I thought of using a controlled current source using a LM334 or similar but could not find any simulation models for it.
Which version of TINA are you using?
Yes, I think the 75 k helped a lot. I found adding a 1n after the 75 k, level out the phase nicely. TINA seems a bit over optimistic on the gain margin (62 dB). Other sim says 44 dB, which I tend to believe a bit more.
Never mind, it looks like yet another bug :x. TINA's automatic PM and GM...
It appears that it should be possible to trim out most of the loading and base current errors by adding a error-compensation resistor after the 75k to the diff amp like shown. Linearity or stability is not affected.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
