UBA2024AT PHILIPS [NXP Semiconductors], UBA2024AT Datasheet - Page 5

• Manufacturer Part Number: UBA2024AT
• Description: Half-bridge power IC for CFL lamps
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
UBA2024
Product data sheet
When entering the sweep mode (V
nominal bridge frequency and sweeps down to the nominal frequency (bridge), set by
R
swing between V
will continue to increase until V
of the sweep time. The voltage on pin SW however will continue to rise until it reaches
supply voltage level.
During this continuous decrease in frequency, the circuit approaches the resonance
frequency of the load, and this causes a high voltage across the load, which ignites the
lamp. The sweep to resonance time should be much larger than the settling time of the
supply voltage on pin HV, to guarantee that the full high-voltage is present at the moment
of ignition. See
Fig 4.
OSC
and C
Oscillator, drivers and output signals
OSC
. During the sweep mode the amplitude of the RC oscillator on pin RC, will
Figure
All information provided in this document is subject to legal disclaimers.
trip(osc)low
Rev. 6.2 — 1 November 2010
5.
bridge
V
drive
drive
and V
V
OUT
half
HS
RC
LS
0
0
0
0
SW
SW
+ 0.4V
SW
+ 0.4V
= 0 V), the bridge oscillator starts at 2.5 times the
trip(osc)high
trip(osc)high
= V
Half-bridge power IC for CFL lamps
. The amplitude of the RC oscillator
trip(osc)high
014aaa658
time
time
time
time
, this determines the end
UBA2024
© NXP B.V. 2010. All rights reserved.
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