uc3848-s08-t Unisonic Technologies, uc3848-s08-t Datasheet
uc3848-s08-t
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uc3848-s08-t Summary of contents
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... Overload protection * Over voltage protection * Leading edge blanking * Soft start ORDERING INFORMATION Ordering Number Normal Lead Free Plating UC3848-D08-T UC3848L-D08-T UC3848-S08-R UC3848L-S08-R UC3848-S08-T UC3848L-S08-T www.unisonic.com.tw Copyright © 2008 Unisonic Technologies Co., Ltd 12.6V, V 8.1V. Lower CC(OFF) -pin’s application as REF for low EMI. R Package ...
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... UC3848 PIN CONFIGURATION PIN DESCRIPTION PIN NO. SYMBOL 1 SS Soft-start 2 FB Feedback 3 CS Controller current sense input OUT Ground 6 GND Output to the gate of external power MOS 7 V Supply voltage Inter 6.3V reference voltage, connected with the filter capacitor REF UNISONIC TECHNOLOGIES CO., LTD www ...
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... UC3848 BLOCK DIAGRAM OVP OLP OTP GND Explain:OLP(Over Load Protection) OVP(Over Voltage Protection) OTP(Over Temperature Protection) UVLO(Under Voltage Latch-Out LEB(Led Edge Blanking) SS(Soft Start) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw V REF 8 UVLO Reference voltage Soft Start Latch S Q Power-Saving R Q Unit ...
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... UC3848 ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage Input Voltage to FB Pin Input Voltage to CS Pin Junction Temperature Operating Temperature Storage Temperature Note Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. ...
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... UC3848 FUNCTIONAL DESCRIPTION The internal reference voltages and bias circuit work at V (1) Soft-Start When every IC power on, driver output duty cycle will be decided by voltage V current sense resistor at beginning. After V depend on V and V . The relation among should more than V start-up phase T OUT ...
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... The maximum switch frequency is 68KHz. The switch frequency is also modulated by output power P operating. Lower switch frequency at lower load can improve IC’s standby efficiency. Switch frequency is decreased minimum at no load, then the UC3848 will operate at Power-Saving mode for Lower standby power. The relation curve between f and P as followed FIG ...
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... UC3848 FUNCTIONAL DESCRIPTION(Cont.) (3) Protection section UC3848 takes on more protection functions such as OLP, OVP and OTP etc. In case of those failure modes for continual 7.2µs (blanking time), the driver is shut down. At the same time, IC enters auto-restart, V driver is reset after V power on again. CC OLP After soft-start phase end (V V > ...
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... Rise edge time of driver output is about 200ns for avoiding Low EMI. When driver output V 2.5V with 200mA source current, and V (5) External power switch MOS transistor Because UC3848 driver output voltage Low level threshold is about 2.5V, User may apply power MOS transistors with bigger threshold. 4N60 is recommended normally. UNISONIC TECHNOLOGIES CO., LTD www ...
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... UC3848 TYPICAL APPLICATION CIRCUIT BD1 TH1 CX1 IC3 UTC 2 7 UC3848 C15 8 1 R11 C3 + C14 Table1 Components Reference description for UC3848 application circuit C12 CC 10nF/1000V C14 CC 100nF/50V C2 CC 33nF/50V CX1 104/275V C5 EC 1000uF/15V C4 CC 22uF/50V C8 EC 68uF/400V C9 EC ...
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... UC3848 TYPICAL CHARACTERISTICS Efficiency vs. Input Voltage at Nominal Load 100 100 150 200 Input Votage (V UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com. 125 250 300 LINEAR INTEGRATED CIRCUIT Efficiency vs. Output Power Efficiency (Vdcin = 120V) Efficiency (Vdcin = 350V) ...
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... UC3848 TYPICAL CHARACTERISTICS(Cont.) Feedback Voltage During Loadjump From 10 100% Load (V =120V) DCIN Ch1 1.00V M 400μs A Ch1 ∫ Startup With Full Load Condition At V DCIN Vc4 and Vout OUT Ch1 2.00V Ch2 5.00V M 10.0ms A Ch1 ∫ UNISONIC TECHNOLOGIES CO., LTD www ...
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... UC3848 UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury ...