LM5021MMX-2 Datasheet, PDF (1/23 Pages) Texas Instruments – LM5021 AC-DC Current Mode PWM Controller

LM5021
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SNVS359D – MAY 2005 – REVISED MARCH 2013
LM5021 AC-DC Current Mode PWM Controller
Check for Samples: LM5021
FEATURES
1
•2 Ultra Low Start-up Current (25 µA maximum)
• Current Mode Control
• Skip Cycle Mode for Low Standby Power
• Single Resistor Programmable Oscillator
• Synchronizable Oscillator
• Adjustable Soft-Start
• Integrated 0.7A Peak Gate Driver
• Direct Opto-Coupler Interface
• Maximum Duty Cycle Limiting (80% for
LM5021-1 or 50% for LM5021-2)
• Slope Compensation for (LM5021-1 Only)
• Under Voltage Lockout (UVLO) with Hysteresis
• Cycle-by-Cycle Over-Current Protection
• Hiccup Mode for Continuous Overload
Protection
• Leading Edge Blanking of Current Sense
Signal
• Packages: VSSOP-8 or PDIP-8
DESCRIPTION
The LM5021 off-line pulse width modulation (PWM)
controller contains all of the features needed to
implement highly efficient off-line single-ended
flyback and forward power converters using current-
mode control. The LM5021 features include an ultra-
low (25 µA) start-up current, which minimizes power
losses in the high voltage start-up network. A skip
cycle mode reduces power consumption with light
loads for energy conserving applications (ENERGY
STAR®, CECP, etc.). Additional features include
under-voltage lockout, cycle-by-cycle current limit,
hiccup mode overload protection, slope com-
pensation, soft-start and oscillator synchronization
capability. This high performance 8-pin IC has total
propagation delays less than 100nS and a 1MHz
capable oscillator that is programmed with a single
resistor.
WHITE SPACE
Simplified Application Diagram
VOUT
+
AC
90 ~ 264 Vac
+
VIN
VCC
LM5021
RT
OUT
SS
CS
COMP GND
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1
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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