AN4376 datasheet(22/37 Pages) STMICROELECTRONICS

Part #	AN4376

Description	10 W wide range non-isolated high power factor LED driver using HVLED815PF

PDF	37 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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22 / 37 page

Measurement results

AN4376

22/37

DocID025380 Rev 1

6.10

LED driver efficiency at different LED load number

Figure 19 shows the efficiency versus the line.

Figure 19. Efficiency versus AC line voltage at different LED load

Varying the number of the LEDs , the efficiency remains comparable with the nominal load,

of course increasing the load to 25 LEDs means increasing the converter output power till

11.5 W. Section 7.7: Thermal measurements on page 29 shows that the HVLED815PF

device is not overeating and is able to support this load properly.

Note:

Important: In this design a sort of short-circuit protection has been previewed, the R25 and

R26 in series with the diode have been added to sense the short-circuit of the output

connectors. If this function is not needed, the two parallel resistors could be removed and

the converter efficiency will increase of 1.5%.

AN4376 Datasheet(PDF) 22 Page - STMicroelectronics