UC2845BDG ON Semiconductor, UC2845BDG Datasheet
UC2845BDG
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UC2845BDG Summary of contents
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UC3844B, UC3845B, UC2844B, UC2845B High Performance Current Mode Controllers The UC3844B, UC3845B series are high performance fixed frequency current mode controllers. They are specifically designed for Off−Line and dc−dc converter applications offering the designer a cost−effective solution with minimal external ...
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MAXIMUM RATINGS Bias and Driver Voltages (Zero Series Impedance, see also Total Device spec) (Note 1) Total Power Supply and Zener Current Output Current, Source or Sink (Note 2) Output Energy (Capacitive Load per Cycle) Current Sense and Voltage Feedback ...
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ELECTRICAL CHARACTERISTICS T is the operating ambient temperature range that applies [Note 8], unless otherwise noted.) A Characteristic OSCILLATOR SECTION Discharge Current (V = 2.0 V) OSC T = 25° (UC284XB, UC384XB) A low ...
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ELECTRICAL CHARACTERISTICS values T is the operating ambient temperature range that applies [Note 12], unless otherwise noted.) A Characteristic PWM SECTION Duty Cycle Maximum (UC284XB, UC384XB) Maximum (UC384XBV) Minimum TOTAL DEVICE Power Supply Current Startup (V = 6.5 V for ...
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Gain 100 1 100 k f, FREQUENCY (Hz) Figure 6. Error Amp Open Loop Gain and Phase versus Frequency 0 - 4 ...
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Source Saturation Ä Ä Ä Ä Ä Ä Ä Ä Ä Ä (Load to Ground) -1 25°C A Ä Ä Ä Ä Ä Ä Ä Ä - 2.0 Ä Ä Ä Ä ...
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The UC3844B, UC3845B series are high performance, fixed frequency, current mode controllers. They are specifically designed for Off−Line and DC−DC converter applications offering the designer a cost−effective solution with minimal external components. A representative block diagram is shown in Figure ...
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V ref 8(14) R Internal 2. Oscillator 4( 1.0mA Voltage Feedback Input 2(3) Error Amplifier Output/ Compensation 1(1) Pin numbers adjacent to terminals are for the 8-pin dual-in-line package. Pin numbers in parenthesis are ...
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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 ...
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Ref 8(14) R Bias Osc 4( Clamp 1 2(3) R Comp/Latch 1.0V 1( 5(9) 1. ≈ ...
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Ref + - + - Comp/Latch Figure 24. Current Waveform Spike Suppression V CC 7(12) 5.0V Ref + - + 7(11 6(10 5(8) Comp/Latch 3(5) Series gate resistor ...
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Ref + - Comp/Latch MCR 101 The MCR101 SCR must be selected for a holding of < 0 simple two transistor circuit can be used in place of the SCR as shown. ...
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MDA 202 115 Vac 0.01 8(14) R Bias 33k R Osc 4(7) 1.0nF + 18k 2(3) 100 EA 150k pF 4.7k 1( Primary: 45 Turns #26 AWG Secondary ± Turns #30 AWG (2 Strands) Bifiliar ...
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UC3845B 8(14) R 2.5V Internal 10k Bias R 3.6V Osc 4(7) 1.0nF + 0.5mA 2R 2(3) R Error Amplifier 1(1) 5(9) 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 UC384xBD UC384xBDG UC384xBDR2 UC384xBDR2G UC384xBD1 UC384xBD1G UC384xBD1R2 UC384xBD1R2G UC384xBN UC384xBNG UC284xBD UC284xBDG UC284xBDR2 UC284xBDR2G UC284xBD1 UC284xBD1G UC284xBD1R2 UC284xBD1R2G UC284xBN UC284xBNG UC384xBVD UC384xBVDG UC384xBVDR2 UC384xBVDR2G UC384xBVD1 T UC384xBVD1G UC384xBVD1R2 UC384xBVD1R2G UC384xBVN UC384xBVNG †For information on ...
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MARKING DIAGRAMS PDIP−8 N SUFFIX CASE 626 8 8 UC384xBN UC384xBVN AWL YYWWG YYWWG 1 1 SOIC−14 D SUFFIX CASE 751A 14 14 UC384xBDG UC384xBVDG AWLYWW AWLYWW 1 1 SOIC−8 D1 SUFFIX CASE 751 8 8 384xB 384xB ALYW ALYWV ...
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F −A− NOTE 2 C −T− N SEATING PLANE 0.13 (0.005) M PACKAGE DIMENSIONS PDIP−8 N SUFFIX CASE 626−05 ISSUE http://onsemi.com 17 ...
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G −T− SEATING 14 PL PLANE 0.25 (0.010 14X 0.58 SOIC−14 CASE 751A−03 ISSUE 0.25 (0.010 ...
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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 ...