Part Number: UCC28780 Other Parts Discussed in Thread: UCC28782 Hello experts:
I am a graduate student and I am participating in a School enterprise project. ACF mobile phone fast charging. Now, I hit a problem that ucc28780 can't start correctly.…
Part Number: UCC28780 Hi, esteemed experts. I use the official UCC28780 simulation circuit given inside simplis to simulate. when I use DC source, the circuit can work properly, Vcs can reach about 0.28V during the first 2μs PWML waveform.
The DC source…
Part Number: UCC28780 Dear Sir,
Refer to the TIDRXG9A.PDF. I have tried to modify the reference model to a 120W-24V-5A power supply.
I'm powered up the unit with 180Vac (Bulk cap 100uF, without PFC).During no-load condition, the output regulation raised…
Part Number: UCC28780 Hello TI expert:
I use UCC28780, Navitas GanIC(NV6115), and MPS SR IC(MP6908A) for active clamp flyback solution.
Follow "Debugging UCC28780 ACF Converter Start-up Issues" document, I have already seen 4 PWML pulse under…
Part Number: UCC28780 Hello,
When I use Ropp=1.1K, Ccs=100pF, the burst mode is stable. And I can see the number of PWML pulse from 2,3,4.....utill power mode.
But when I change Ropp 1.1K → 301R(I need higher opp trig point at high line), the burst mo…
Hi Mo Mo,
The latest calculator version on TI.com is SLUC664C , while you are using is SLUC664B version. Could you please try to use the latest version.
BTW, it's not recommend to chose ACF for a 7W design. it will not brings you too much benefits for…
Part Number: UCC28780 Other Parts Discussed in Thread: UCD3138 Hello,
I am a student doing a project that involves making a DC to DC flyback converter with some questions about the UCC28780. We were interested in the ZVS functionality of this chip was…
Part Number: UCC28780 Hi expert:
One of the current waveforms of my secondary synchronous rectifier has achieved ZCS, and the other has not. The two waveforms form a cycle. I don’t know why the secondary synchronous rectifier is turned on twice in Figure…
Part Number: UCC28780 Hello expert:
The main switch tube can realize zero voltage turn-on, as shown in Figure 2. However, when the switch is turned off, Vgs (L) and VDS (L) oscillate relatively large, as shown in Figure 3.
Figure 1
Figure 2
Figure…
Part Number: UCC28780 When Vin increases to 120VDC, Ipri waveform is normal, as shown in Figure 1 .
Figure 1
When Vin increases to 200VDC, there are two forms of Ipri waveform, and the Ipri peak is stable, as shown in Figure 2.
Figure 2
When Vin increases…
