NCL30051LEDGEVB ON Semiconductor, NCL30051LEDGEVB Datasheet - Page 17

• Manufacturer Part Number: NCL30051LEDGEVB
• Description: Power Management IC Development Tools 90-265VAC 60W ISO CC EVB
• Manufacturer: ON Semiconductor
• Type: Power Factor Correctionr

Specifications of NCL30051LEDGEVB

• Rohs: yes
• Product: Evaluation Boards
• Tool Is For Evaluation Of: NCL30051
• Input Voltage: 90 VAC to 265 VAC
• Output Voltage: 35 V to 50 V
• Output Current: 1.5 A

Dimming Limitations
ratio for 120 and 230 Vac within the V
graphs of Figure 8 above. It is not recommended to take
PWM dimming to zero as this will ultimately result in the
power supply going into a start−stop “hiccup” mode due to
controller V
(of rated max current) due to depletion of primary circuitry
V
Output Ripple
amount of bulk capacitance (C4 and C5), and the ripple on
CC
PWM dimming is effective down to less than 5% duty
The output current ripple is primarily a function of the
.
CC
depletion. Analog dimming is limited to 10%
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0
120 Vac; Analog Dim
230 Vac; Analog Dim
10
120 Vac; PWM Dim
f
ranges shown in the
Figure 14. Power Factor versus Dimming
20
PERCENT OF FULL LOAD (%)
30
http://onsemi.com
230 Vac; PWM Dim
40
19
50
the bulk will be reflected to the output by the product of the
transformer turns ratio and the half−bridge switch voltage
reduction ratio, or, as mentioned previously, 5 x 2 = 10. Since
the power factor control loop must have a low bandwidth to
produce high power factor, the 120 Hz bulk ripple will
naturally be transferred to the output proportionally. In this
example, the use of two bulk capacitors of 82 mF in series,
giving a total capacitance of 41 mF, was adequate to keep the
output current ripple below 10%. Figure 15 shows the
output current ripple with an LED string of V
magnitude of the ripple is only slightly affected by V
line voltage.
60
70
80
90
100
f
= 40 V. The
f
and