STEVAL-ILL013V1 Datasheet, PDF (20/43 Pages) STMicroelectronics – 80 W offline LED driver with PFC

UM0670
Measurement
Figure 14. Output LED current for different LED voltages (I_LED = 350 mA)
450
400
350
LED 300
current
[mA] ²⁵⁰
200
150
100
50
0
VLED v s. ILED for nominal LED current 350 mA
174
193
211
230
250
LED voltage [V]
350 mA
AM00399
Figure 15 shows the output LED current waveform for the LED current of 700 mA. The
current ripple is, in this case, 333 mA and the switching frequency for the modified buck
converter is 69 kHz. The input voltage was 230 AC and 6 LEDs were used as the load
(OSTAR LED LE UW E3B see Section 11: References and related materials: 6). The output
LED current accuracy for the different LED voltages is shown in Figure 16.
Figure 15. Output LED current waveforms (I_LED = 700 mA)
Doc ID 15327 Rev 2
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