FEATURES
s HIGH ACCURACY CURRENT CONTROLLED OSCILLATOR s INTEGRATED BOOTSTRAP DIODE s CLAMPING ON VS. s SO16, DIP 16 PACKAGES DESCRIPTION
In order to ensure voltage ratings in excess of 600V, SO16N DIP16 ORDERING NUMBERS: L6574D L6574 The device is intended to drive two power MOSFETS, in the classical half bridge topology, ensuring all the features needed to drive and properly control a fluorescent bulb. Also, an OP AMP is available to implement closed loop control of the lamp current during normal lamp burning. An integrated bootstrap section, eliminating the normally required bootstrap diode and the zener clamping on Vs, makes the L6574 well suited for low cost applications where few additional components are needed to build a high performance ballast. BLOCK DIAGRAM OPOUT OPINOPIN+ OP AMP + - Imin VREF RING Imax VREF RPRE VCO Cf VS UV DETECTION BOOTSTRAP DRIVER HVG DRIVER CONTROL LOGIC DEAD TIME Ifs Ipre + Vthpre - + - DRIVING LOGIC LEVEL SHIFTER VS LVG DRIVER + VTHE - + VTHE - VBOOT HVG OUT LVG GND EN1 EN2 CPRE D97IN493A H.V.
STMicroelectronics
