NXP Semiconductors
UBA2021
630 V driver IC for CFL and TL lamps
• Where:
• fB = bottom frequency.
• fff = feed-forward frequency.
• fcm = frequency due to capacitive mode detection.
• Preheat time: t ph = 1----5C---0-C--n-P--F-- × -R3---0-R--K-R---E-Ω--F-
• Ignition time: tign = 11----56- × t ph
• Non-overlap time: tno = 1.4µs × -R-3---R0---Rk---EΩ---F-
12. Application information
L1
DS1
R1
mains
supply
DS2
C3
C2
DS3
DS4
C4
Fig 7. Application diagram
Vin
T1
lamp
L2
C5
T2
Rshunt
RRHV
490 kΩ
G1
2
S1
3
100 nF
CS7
FS
Cboot
1
DS7
CS4 DS6
G2
6
VS 5
CS9
RHV
13
14 CI
CCI
100 nF
8 CP
UBA2021 12 CF
CCP
100 nF
CCF
100 pF
10 RREF RRREF
30 kΩ
SGND
7
9 11
PGND RS
mgs994
UBA2021_4
Product data sheet
Rev. 04 — 25 July 2008
© NXP B.V. 2008. All rights reserved.
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