Datasheet

UBA2071_A_1 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 01 — 23 June 2008 28 of 35
NXP Semiconductors
UBA2071; UBA2071A
Half bridge control IC for CCFL backlighting
12. Application information
Figure 19 shows an example backlighting configuration, where the inverter is supplied
from a high voltage DC source and the IC is supplied by means of a ∆V/∆t supply (C14,
C15, Z1 and D1). Two lamps are connected, each to the output of its own transformer. The
leakage inductance of this transformer provides the ballast impedance for the lamps. An
analog voltage is converted to a PWM signal to provide for the desired brightness level.
Lamp short detection is done via the lamp voltage sensing, D13 and D23, and the
NONFAULT pin.
Figure 20 shows an example of a balanced application using one UBA2071 and one
UBA2073.