Designing a high PF wide range LED driver with the HVLED815PF

AN4496

16/18

DocID026370 Rev 1

2.9

OVP protection

Equation 35

2.10

AC modulation

To obtain the high power factor and low THD, a signal proportional to rectified mains is

applied to the ILED pin.

The other components of the network that switching the range can be calculated, but the

non-linear behavior of Qr due the modulation of the Qr collector requires a fine tuning of the

network; using the next recommended value for the components, the only value to be

calculated is R3 to optimize the modulation at 85 - 90 V.

Equation 36

With:

Rp1 = Rp2 = 180 k



Rps = 120 k



Rpc = 51 k



Rpe = 15 k



Rr1 = Rr2 = 120 k



Rr3 = 62 k



Cr3 = 4.7 µF

Dr = BZV55-C20

Qr = MMBTA42

Real value used:

Rfb = 16k

