EVAL6569 Datasheet, PDF (2/14 Pages) Panasonic Semiconductor – THE L6569 A NEW HIGH VOLTAGE IC DRIVER FOR ELECTRONIC LAMP BALLAST

AN880 APPLICATION NOTE
THE L6569 AND ITS APPLICATIONS
The L6569
The L6569 is able to directly control a symmetric
half bridge inverter of a fluorescent lamp ballast,
or a low voltage halogen lamp transformer.Two
270mA buffers drive the inverter MOSFETs in
complementary fashion with a 1.25µs built-in
dead time to prevent cross conduction. The buffer
for the upper Mosfet is driven through a 600V
level shifter realized in BCD off line technology.
The oscillator, similar to a CMOS 555 timer, oper-
ates from 25 to 150 kHz with a +/-5% maximum
tolerance. The internal 15V shunt regulator has a
9V Under Voltage Lock Out with an 1V hysteresis,
Figure 3: Block diagram of the L6569.
and the circuit requires only 150 µA at power up.
The L6569 integrates a high voltage Lateral
DMOS transistor in place of the usual external di-
ode [2] to charge the bootstrap capacitor for the
upper buffer. Figure 5 shows DMOS operating as
a synchronous rectifier.
The applications
The primary application for the L6569 is the Com-
pact Fluorescent Lamp. With the oscillator, the
supply and the Mosfet drivers it is the core of the
application, and designers can customize the cir-
cuit to their requirements.
VS
BOOT
UVLO
RF
CF
CHARGE
PUMP
LEVEL
SHIFTER
LOGIC CONTROL
with DEAD TIME
GND
HIGH
SIDE
DRIVER
HVG
OUT
LOW
SIDE
DRIVER
LVG
Figure 4: Basic application diagram using the L6569 and two STD4NK50Z MOSFETs.
AC LINE
180KΩ
10µF
10KΩ
10µF
1nF
100nF
22Ω
L6569
22Ω
STD4NK50Z
LAMP
2/14
D02IN1385