L I N D
O C
# :
1562
LX1562/1563
S
E C O N D
-G
E N E R AT I O N
P
O W E R
F
A C T O R
C
O N T R O L L E R
T
H E
I
N F I N I T E
P
O W E R
O F
I
N N O VA T I O N
P
R O D U C T I O N
D
A T A
S
H E E T
DESCRIPTION
The LX1562 is a second-generation
family of power factor correction
controllers using a discontinuous mode
of operation. They are optimized for
electronic ballast applications. Many
improvements have been made over
the original SG3561A controller
introduced by Silicon General Semicon-
ductor in 1992.
New features include the addition of
an internal start-up circuit eliminating
bulky external components while
allowing independent boost converter
operation. Addition of internal current
sense blanking eliminating the need for
an external R/C filter network. Internal
clamping of the error amplifier and
multiplier outputs improves turn on
overshoot characteristics and current
limiting. Special circuitry has also been
added to prevent no load runaway
conditions. And finally, output drive
clamps limiting power MOSFET gate
drive independent of supply voltage
greatly enhance the products practical
application.
Although the IC design has been
optimized for electronic ballast applica-
tions, it can also be used for power
factor correction in lower power (typ <
300W) AC-DC converters. One unique
feature of the device is encompassed
by the addition of internal logic
circuitry to detect zero crossing of the
inductor current thus maintaining the
discontinuous current mode of opera-
tion. This feature prevents large
current gaps from appearing thereby
minimizing distortion and enhancing
power factor correction.
K E Y F E AT U R E S
s
INTERNAL START-UP CIRCUIT
s
INTERNAL CURRENT SENSE BLANKING
s
IMPROVED MICROPOWER START-UP
CURRENT
(300µA max.)
s
CLAMPED E.A. OUTPUT FOR LOWER
TURN-ON OVERSHOOT
s
MULTIPLIER CLAMP LIMITS MAXIMUM
INPUT CURRENT
s
INTERNAL OVERVOLTAGE PROTECTION
REPLACES BUILT-IN C.S. OFFSET
s
PWM OUTPUT CLAMP LIMITS MOSFET
GATE DRIVE VOLTAGE
s
INCREASED UVLO HYSTERESIS REDUCES
START-UP TIMING
(LX1562 only)
s
LOW OPERATING CURRENT CONSUMPTION
s
INTERNAL 1.5% REFERENCE
s
TOTEM POLE OUTPUT STAGE
s
AUTOMATIC CURRENT LIMITING OF BOOST
STAGE
s
DISCONTINUOUS MODE OF OPERATION
WITH NO CURRENT GAPS
s
NO SLOPE COMPENSATION REQUIRED
PRODUCT HIGHLIGHT
T
YPICAL
A
PPLICATION OF THE
LX1562
IN AN
80W
F
LUORESCENT
L
AMP
B
ALLAST WITH
A
CTIVE
P
OWER
F
ACTOR
C
ONTROL
450µH
61T #22AWG
100k
�½W
L1
R3
7T
D5
R4
22k
1N4935
8
V
IN
5
I
DET
A P P L I C AT I O N S
s
ELECTRONIC BALLAST
s
SWITCHING POWER SUPPLIES
MR854
D7
V
BOOST
230V
D1
D3
1N4004
1N4004
AC+
EMI FILTER
120V
AC
AC-
2.2M
R1
1%
C1 1µF
250V
C2
22µF
R10
4.7M
R7
FLOURESCENT LAMP BALLAST
D6
1N4148
47Ω
R5
R9 620k
C5
0.1µF
1MΩ
1%
Q1
1RF730
A
VA I L A B L E
O
P T I O N S
Part #
LX1562
LX1563
Start-Up
Voltage
13.1V
9.8V
PER
P
A R T
#
Hysteresis
Voltage
5.2V
2.1V
LX1562
OUT 7
3
MULT
IN
D2
D4
COMP
INV
2
1
4
C6
100µF
400V
11k
1%
R6
1.3Ω
R8
1N4004
1N4004
0.1µF
29k
R2
1%
C3
C4
.01µF
GND
6
C.S.
3x
1/4W
Note: Thick trace on schematic shows high-frequency, high-current path in circuit.
Lead lengths must be minimized to avoid high-frequency noise problems.
PA C K A G E O R D E R I N F O R M AT I O N
T
A
(°C)
0 to 100
0 to 100
M
Plastic DIP
8-pin
LX1562IM
LX1563IM
DM
Plastic SOIC
8-pin
LX1562IDM
LX1563IDM
Note: All surface-mount packages are available in Tape & Reel.
Append the letter "T" to part number. (i.e. LX1562IDMT)
F O R F U R T H E R I N F O R M AT I O N C A L L ( 7 1 4 ) 8 9 8 - 8 1 2 1
Copyright © 1996
Rev. 1.3 12/96
11861 W
ESTERN
A
VENUE
, G
ARDEN
G
ROVE
, CA. 92841
1
MICROSEMI [ MICROSEMI CORPORATION ]
