Harman Kardon MAS 101, Руководство по обслуживанию

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Product Specification
Power Factor Controller
SG6961
© System General Corp. www.sg.com.tw • www.fairchildsemi.com
Version 1.3.1 (IRO33.0028.B6)
September 24, 2007
FEATURES
„
Boundary Mode PFC Controller
„
Low Input Current THD
„
Controlled On-Time PWM
„
Zero-Current Detection
„
Cycle-by-Cycle Current Limiting
„
Leading-Edge Blanking Instead of RC Filtering
„
Low Start-up Current (10µA Typical)
„
Low Operating Current (4.5mA Typical)
„
Feedback Open-Loop Protection
„
Programmable Maximum On-Time (MOT)
„
Output Over-Voltage Clamping Protection
„
Clamped Gate Output Voltage 16.5V
APPLICATIONS
„
Electric Lamp Ballasts
„
AC-DC Switching Mode Power Converter
„
Open-Frame Power Supplies and Power Adapters
„
Flyback Power Converters with ZCS/ZVS
DESCRIPTION
The SG6961 is an 8-pin boundary mode PFC controller IC
intended for controlling PFC pre-regulators. The SG6961
provides a controlled on-time to regulate the output DC
voltage and achieve natural power factor correction. The
maximum on-time of the external switch is programmable
to ensure safe operation during AC brownouts. An
innovative multi-vector error amplifier is built in to
provide rapid transient response and precise output
voltage clamping. A built-in circuit disables the controller
if the output feedback loop is opened. The start-up current
is lower than 20µA and the operating current is under
4.5mA. The supply voltage can be up to 20V, maximizing
application flexibility.
TYPICAL APPLICATION
ZCD
MOT
GND
CS
GD
INV COMP
VCC
SG6961
VAC
Vo
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