AN10961_15 Datasheet, PDF (48/57 Pages) NXP Semiconductors – Dimmable CFL using the UBA2027X family

NXP Semiconductors
AN10961
Dimmable CFL using the UBA2027X family
8.3.4 Voltage doubler and voltage source charge pump with ICF and
autotransformer 120 V
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Fig 34. Single power feedback with single stage EMI filter, improved crest factor lower
stress on bus voltage at light load and autotransformer to improve efficiency
Typical applications:
• UBA20270; 120 V mains; up to 23 W
Advantages:
• Low component count
• Higher power medium-voltage lamps
• Better efficiency
• Crest factor = 2.2
Disadvantages:
• High lamp voltage sensitivity
• Two buffer capacitors
• Extra winding on resonant transformer
AN10961
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 8 June 2012
© NXP B.V. 2012. All rights reserved.
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