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Part Number: UCC3818 Hi,
It is said in SLUS395K that maximum multiplier current is 315 uA for Figure. 9 but with RAC given as 750kOhm, IAC at Vmin of 85 V becomes 158 uA. If V_VFF is a 2:1 current mirror connected to the RC, then magnitude of VFF voltage…
Part Number: UCC3818 Hi,
For the example shown in Figure 9. of SLUS395K, I calculate the phase of margin of current loop (explained in 8.2.2.5) to be 23 deg with the values of capacitors in Figure. 9 and 36 deg with the values calculated from equations…
Part Number: UCC3818 Hi,
Does equation (19) in SLUS395K miss a factor of 2? Should it be like this:
fVI^2 = PIN / (4π^2 × ΔVVAOUT × VOUT × RIN × COUT × Cf)
I checked the given reference [slup106] and there exists…
Part Number: UCC3818 In the app note of SLUS395K, it is mentioned that VRSENSE is selected to give a dynamic operating range of 1.25 V, what are the downsides of going way higher or way lower than this value for example going to 14 V or 0.05 V?
Why is…
Part Number: UCC3818 Hi, Figure 2 page 2 of the below App note shows R1, R2 and Q1....the idea is that Q1 turns off when VAOUT goes less than 1V...but would you agree, the circuit shown could not reliably do that.....instead a comparator would be needed…
Part Number: UCC3818 Other Parts Discussed in Thread: UC3854 Hi,
Hope thsi finds you well
Please advise of a App Note for feedback loop calculation with UCC3818?
Part Number: UCC3818 Hi,
Some ti.com PFC controllers require a resistor to be fitted between VREF pin and IAC pin, such that the zero crossing distortion is avoided.
How is this done for the UCC3818?
Part Number: UCC3818 Hi Expert,
Will need to clarify why there is no DRVOUT during AC input lost.
Conditions:
--PFC stage is running under AC input
--Turn off the AC input for serval AC cycle (60Hz) then turn on the AC input back
--VCC is in the biased…
Part Number: Hi Expert,
The engineer is asking how to run the UCC3818 into the open loop mode.
They are thinking to inject a DC level into CAOUT pin.
Then PWM width can programmed by the this DC level.
Pls advice whether this is workable or not.
…
