UC3845D ON Semiconductor, UC3845D Datasheet
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UC3845D
Specifications of UC3845D
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UC3845D Summary of contents
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... Internally Trimmed Reference with Undervoltage Lockout • High Current Totem Pole Output • Input Undervoltage Lockout with Hysteresis • Low Startup and Operating Current • Direct Interface with ON Semiconductor SENSEFETt Products • Pb−Free Packages are Available V ref 8(14) Reference R V ref ...
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MAXIMUM RATINGS Rating Total Power Supply and Zener Current Output Current, Source or Sink (Note 1) Output Energy (Capacitive Load per Cycle) Current Sense and Voltage Feedback Inputs Error Amp Output Sink Current Power Dissipation and Thermal Characteristics D Suffix, ...
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ELECTRICAL CHARACTERISTICS Characteristics ERROR AMPLIFIER SECTION (continued) Unity Gain Bandwidth (T = 25°C) J Power Supply Rejection Ratio ( Output Current Sink ( Source ...
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NOTE: Output switches at one−half the oscillator frequency. 1 100 k 200 OSCILLATOR FREQUENCY (Hz) osc Figure 2. Timing Resistor versus Oscillator Frequency 2.55 ...
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T = 125°C A − 25°C A − REFERENCE SOURCE CURRENT (mA) ref Figure 8. Reference Voltage Change versus Source Current ...
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Figure 14. Output Cross Conduction PIN FUNCTION DESCRIPTION Pin 8−Pin 14−Pin Function 1 1 Compensation 2 3 Voltage Feedback 3 5 Current Sense − GND 6 10 Output ...
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The UC3844, UC3845 series are high performance, fixed frequency, current mode controllers. They are specifically designed for Off−Line and DC−to−DC converter applications offering the designer a cost effective solution with minimal external components. A representative block diagram is shown in ...
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V ref 8(14 Oscillator 4( 1.0mA + − Voltage Feedback Input 2(3) Error Output Amplifier Compensation 1(1) Pin numbers in parenthesis are for the D suffix SOIC−14 package. Capacitor C T Latch ...
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Undervoltage Lockout Two undervoltage lockout comparators have been incorporated to guarantee that the IC is fully functional before the output stage is enabled. The positive power supply terminal (V and the reference output (V CC each monitored by separate comparators. ...
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R Bias + − − OSC + 4(7) V Clamp 1.0mA + − − 2(3) Comp/Latch R 1.0V 1(1) R1 5(9) 1. − 0.33 x ...
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V CC 7(12) + 5.0V − ref + − + − + 7(11) R − 6(10 − 5( Comp/Latch 3(5) Series gate resistor R will damp any high frequency parasitic oscillations g caused by the ...
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MDA 202 115VA C 8(14) 0.01 Bias 33k 4(7) OSC + 1.0nF 18k 2(3) + − EA 4.7k 1(1) T1 − Primary: 45 Turns # 26 AWG Secondary ± Turns # 30 AWG T1 − T1 ...
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UC3845 8(14) R Internal Bias 2.5V R 10k 4(7) Oscillator + 1.0nF 0.5mA 2R + 2(3) − Error R 1(1) Amplifier The capacitor’s equivalent series resistance must limit the Drive Output current to 1 additional series resistor may ...
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... ORDERING INFORMATION Device Operating Temperature Range UC3844D UC3844DG UC3844DR2 UC3844DR2G UC3844N UC3844NG UC3845D UC3845DG UC3845DR2 UC3845DR2G UC3845N UC3845NG UC2844D UC2844DG UC2844DR2 UC2844DR2G UC2844N UC2844NG UC2845D UC2845DG UC2845DR2 UC2845DR2G UC2845N UC2845NG †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. PDIP− ...
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F −A− NOTE 2 C −T− N SEATING PLANE 0.13 (0.005) M −A− −B− −T− SEATING 14 PL PLANE 0.25 (0.010 PACKAGE ...
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... *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. SENSEFET is a trademark of Semiconductor Components Industries, LLC. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein ...