UC3845 STMicroelectronics, UC3845 Datasheet
UC3845
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UC3845 Summary of contents
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... BLOCK DIAGRAM (toggle flip flop used only in U3844 and UC3845) October 1998 UC2842/3/4/5 UC3842/3/4/5 CURRENT MODE PWM CONTROLLER ...
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... UC2842N UC2843N UC2844N UC2845N UC3842N UC3843N UC3844N UC3845N Min id ip max. Value Unit 30 V Self Limiting – 0 725 mW – 150 C 300 C Minidip SO14 UC2842D UC2843D UC2844D UC2845D UC3842D UC3843D UC3844D UC3845D SO14 Unit 100 165 C ...
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ELECTRICAL CHARACTERISTICS (Unless otherwise stated, these specifications apply for -25 < for UC2824X; 0 < T < for UC384X; V amb Symbo l Parameter V Output Voltage REF Line Regulation V REF Load Regulation V ...
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... PIN3 5. Adjust V above the start threshold before setting Output frequency equals oscillator frequency for the UC3842 and UC3843. Output frequency is one half oscillator frequency for the UC3844 and UC3845. 4/11 UC284X T est Cond ition s Min. T yp. Max. Min. T yp. Max. ...
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Figure 1 : Error Amp Configuration. Error amp can source or sink up to 0.5mA Figure 2 : Under Voltage Lockout. During Under-Voltage Lockout, the output driver is biased to sink minor amounts of current. Pin 6 should be shunted ...
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UC2842/3/4/5-UC3842/3/4/5 Figure 4. 1.72 for R > Figure 6 : Timing Resistance vs. Frequency. Figure 8 : Error Amplifier Open-loop Frequency Response. 6/11 Figure 5 : Deadtime vs > 5K ...
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Figure 9 : Open Loop Test Circuit. High peak currents associatedwith capacitive loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close Figure 10 : Shutdown Techniques. Shutdown of the UC2842 can be accomplished by two methods; ...
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UC2842/3/4/5-UC3842/3/4/5 Figure 11 : Off-line Flyback Regulator. Power Supply Specifications 1. Input Voltage : 95 VAC to 130 VAC (50 Hz/60 Hz) 2. Line Isolation : 3750 V 3. Switching Frequency : 40 KHz 4. Efficiency @ Full Load : ...
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DIM. MIN.. TYP. MAX.. MIN.. A 1.75 a1 0.1 0.25 0.004 a2 1.6 b 0.35 0.46 0.014 b1 0.19 0.25 0.007 C 0 (typ.) D (1) 8.55 8.75 0.336 E 5.8 6.2 0.228 e 1.27 e3 7.62 ...
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UC2842/3/4/5-UC3842/3/4/5 mm DIM. MIN. TYP. MAX. MIN. A 3.3 a1 0.7 0.028 B 1.39 1.65 0.055 B1 0.91 1.04 0.036 b 0.5 b1 0.38 0.5 0.015 D 9.8 E 8.8 e 2.54 e3 7.62 e4 7.62 F 7.1 I 4.8 ...
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... No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMi- croelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics ...