UBA2025 NXP Semiconductors, UBA2025 Datasheet - Page 11

• Manufacturer Part Number: UBA2025
• Description: Cfl Power Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
11. Application information
UBA2025_1
Product data sheet
11.1 Design equations
•
•
•
•
•
•
Bottom frequency:
Feed forward frequency:
Where:
– X1 = 3.68
– X2 = 22.28
– t = 0.4 s
– R
– C
– V
– V
– R
Operating frequency = f
Where:
– f
– f
– f
Preheat time:
Ignition time:
Non-overlap time:
t
t
t
f
f
ign
no
ph
btm
ff
btm
ff(max)
cm(max)
=
=
=
ref
i(VDC)
=
int
par
HV
=
1.4 s
----------------- -
150 nF
------------------------------------------------------------------------------------------------------------------------- Hz
2
= 3 k
= 2.5 V
= bottom frequency
15
----- -
16
= 4.7 pF
= 560 K (see
---------------------------------------------------------------------------------------------------------- - Hz
2
C
= maximum feed forward frequency
CP
= 300 V (nominal)
= maximum frequency due to capacitive mode detection
t
C
ph
C
f
---------------
30 k
f
+
s
R
--------------- s
30 k
+
R
C
ref
Rev. 01 — 16 October 2009
C
ref
par
par
Figure
btm(max)
X 2 V
---------------------------------------- - R
X 1
1
1
6)
V
, f
i VDC
R
ff(max)
ref
IREF
R
, and f
–
HV
R
int
–
cm(max)
int
+
t
+
t
UBA2025
© NXP B.V. 2009. All rights reserved.
CFL power IC
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