UBA2021T/N2,518 NXP Semiconductors, UBA2021T/N2,518 Datasheet - Page 5

• Manufacturer Part Number: UBA2021T/N2,518
• Description: IC CFL DRIVER 630V 14-SOIC
• Manufacturer: NXP Semiconductors
• Type: CFL/TL Driverr

Specifications of UBA2021T/N2,518

• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Frequency: 41.21 ~ 44.59kHz
• Current - Supply: 1mA
• Voltage - Supply: 630V
• Operating Temperature: -40°C ~ 150°C
• Driver Type: CFL, Fluorescent TL Drivers
• Operating Supply Voltage: 630 V
• Maximum Operating Temperature: + 150 C
• Mounting Style: SMD/SMT
• Maximum Output Current: 35 mA
• Maximum Power Dissipation: 500 mW
• Minimum Operating Temperature: - 40 C
• Supply Current: 1 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Details
• Other names: 568-4929-2; 935211250518; UBA2021T/N2,518; UBA2021T/N2-T; UBA2021T/N2-T

NXP Semiconductors
UBA2021_4
Product data sheet
7.5 Ignition state
7.6 Failure to ignite
7.7 Transition to the burn state
7.8 Feed-forward frequency
The RS monitoring function changes from V
protection at the end of the preheat time. Normally this results in a further frequency
decrease down to the bottom frequency f
frequency in the ignition state is less than that in the preheat mode. During the downward
frequency sweep the circuit sweeps through the resonant frequency of the load. A high
voltage then appears across the lamp. This voltage normally ignites the lamp.
Excessive current levels may occur if the lamp fails to ignite. The IC does not limit these
currents in any way.
Assuming that the lamp has ignited during the downward frequency sweep, the frequency
normally decreases to the bottom frequency. The IC can transit to the burn state in two
ways:
The bottom frequency is determined by R
During burn state a feed-forward mechanism ensures that the lamp power will not
increase above the maximum allowed value due to an increased mains voltage. In the
feed-forward range the UBA2021 driver IC can be configured in such a way that the
application is optimized for close to constant lamp power. Above a defined voltage level
the oscillation frequency also depends on the supply voltage of the half-bridge (see
Figure
through R
average value of the current through R
lower limit set by f
mA) the feed-forward frequency is clamped. In order to prevent feed-forward of ripple on
1. In the event that the bottom frequency is not reached, transition is made after
2. As soon as the bottom frequency is reached.
Fig 5.
reaching the ignition time t
6). The current for the current controlled oscillator is derived from the current
Operation in the preheat mode
RHV
in the feed-forward range. The feed-forward frequency is proportional to the
B
. For currents beyond the operating range (i.e. between 1.0 mA and 1.6
f
Rev. 04 — 25 July 2008
start
f
B
ign
preheat state
.
RHV
B
RREF
(approximately 43 kHz). The rate of change of
within the operating range of I
RS(ctrl)
and C
ignition
state
630 V driver IC for CFL and TL lamps
regulation to capacitive mode
CF
.
time
burn state
mgs992
UBA2021
© NXP B.V. 2008. All rights reserved.
i(RHV)
, given the
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