September 2014

DocID026370 Rev 1

1/18

18

AN4496

Application note

How to get a high power factor with the HVLED815PF device

Stefano Signoria

Introduction

The standard application of the HVLED8xxPF (HVLED807PF, HVLED815PF) is a constant

datasheet (section 4.5 Constant current operation), does not depend on the value or the

implementation.

Two methods of implementing the high power factor (HPF) based on the HVLED8xxPF

family are current in use: the current sense modulation and ILED modulation. In either case

the input voltage after rectification is not smoothed and the waveform on the bulk capacitor

With the first method, the additional circuitry in Figure 1 applies a DC offset and

This solution is described in detail in 1. of Section 3.

The second one, shown in Figure 2, applies a modulation of the ILED pin proportional to the

details). This application note describes how to modify the basic circuit to support wide input

range applications.

1

Figure 1. CS HPF; additional components

Figure 2. ILED HPF; additional component

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