AN10958_15 Datasheet, PDF (47/56 Pages) NXP Semiconductors – Fluorescent lamp driver with PFC using the UBA2015/16 family

NXP Semiconductors
AN10958
Fluorescent lamp driver with PFC using the UBA2015/16 family
VBUS
Celectrode
GHHB
VDD _SHHB
Lres
OCpreheat
HALF-BRIDGE
CONTROLLER
saturation
8.5 μA
480 mV
GLHB
SLHB
2.5 V
UBA2016A
Cres
RSLHB
Celectrode
Cdc
019aaa656
L_res: limits the lamp current in normal operation.
C_res: generates the ignition voltage.
C_electrode: reduces the electrode current in nominal operation.
R_SLHB: limits the half-bridge current during preheat and sets the saturation current.
Fig 35. The SLHB pin and conventional heating
4.4.2 Inductive mode heating
See Figure 36. In Preheat state, the half-bridge current flows through L_res and the
electrodes of the lamp (no current flows through C_DC). Once the lamp is ignited, the
half-bridge current also flows through the lamp and the resonant tank (L_resC_res) is
damped. The current though the C_DC capacitor is equal to the lamp current, as a result the
lamp current can easily be measured.
This type of circuit is used if lamp current control is required, such as dimming.
AN10958
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 9 August 2012
© NXP B.V. 2012. All rights reserved.
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