DS12866 Rev 1

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HVLED007

Application information

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constant along a line half-cycle. This is a normal design target in any Hi-PF converter, thus

of the signal on the current sense input CS. This value, listed among the parameters in

"Section 3: Electrical characteristics", is accurate because it determines the maximum

power deliverable by the converter and is used to design the saturation current of the

flyback transformer (see "Section 4.7: Current sensing input (pin CS). Sense resistor (Rs)

selection").

of non-idealities please refer to Reference 1.

Figure 7. Shape of the current reference Vcsref(θ) (5) at different input voltages (i.e.

Kv values)

4.3

Operation of a Hi-PF QR flyback converter based on the

HVLED007

The ICS circuit changes the profile of the peak current envelope along a line half-cycle (as

shown in Figure 7) and this slightly changes the timing and the electrical quantities in the

converter in steady-state operation as compared to those of a traditionally controlled Hi-PF

QR flyback converter [Reference 2]. There are differences in the peak and rms currents but