Datasheet Texas Instruments UC2845N — Datenblatt

HerstellerTexas Instruments
SerieUC2845
ArtikelnummerUC2845N
Datasheet Texas Instruments UC2845N

Strommodus-PWM-Controller 8-PDIP -40 bis 85

Datenblätter

UCx84x Current-Mode PWM Controllers datasheet
PDF, 3.8 Mb, Revision: E, Datei veröffentlicht: Jan 6, 2017
Auszug aus dem Dokument

Preise

Status

Lifecycle StatusActive (Recommended for new designs)
Manufacture's Sample AvailabilityYes

Verpackung

Pin8
Package TypeP
Industry STD TermPDIP
JEDEC CodeR-PDIP-T
Package QTY50
CarrierTUBE
Device MarkingUC2845N
Width (mm)6.35
Length (mm)9.81
Thickness (mm)3.9
Pitch (mm)2.54
Max Height (mm)5.08
Mechanical DataHerunterladen

Parameter

Control MethodPeak Current Mode
Duty Cycle(Max)50 %
Frequency(Max)500 kHz
Frequency(Min)26 kHz
Gate Drive(Typ)1 A
Operating Temperature Range-40 to 85 C
Package GroupPDIP
RatingCatalog
Special FeaturesError Amplifier,Multi-topology
TopologyBoost,Buck,Flyback,Forward
UVLO Thresholds On/Off8.4/7.6 V
Vin(Max)400 V
Vin(Min)8.4 V

Öko-Plan

RoHSCompliant

Anwendungshinweise

  • U-100A UC3842/3/4/5 Provides Low-Cost Current-Mode Control
    PDF, 507 Kb, Datei veröffentlicht: Sep 5, 1999
    The fundamental challenge of power supply design is to realize simultaneously two conflicting objectives: good electrical performance and low cost. The UC3842/3/4/5 control ICs are integrated pulse-width modulators (PWMs). These inexpensive IC controllers provide all the performance advantages of current-mode operation. In addition the UC3842 series is optimized for efficient power-sequencing of
  • Understanding Buck Power Stages In Switchmode Power Supplies
    PDF, 173 Kb, Datei veröffentlicht: Mar 4, 1999
    A switching power supply consists of the power stage and the control circuit. The power stage performs the basic power conversion from the input voltage to the output voltage and includes switches and the output filter. This report addresses the buck power stage only and does not cover control circuits. Detailed steady-state and small-signal analysis of the buck power stage operating in continuous
  • DN-40 The Effects of Oscillator Discharge Current Variations on Maximum Duty
    PDF, 39 Kb, Datei veröffentlicht: Sep 5, 1999
    This design note details programming frequency and maximum duty cycle using the UC3842 and UC3842-A PWM oscillator ICs. Simplified equations are used to develop obtainable ranges for parameters over IC tolerances.
  • DN-27 UC1842/UC1842A Family - Summary of Functional Differences
    PDF, 21 Kb, Datei veröffentlicht: Sep 5, 1999
    The UC1842A/3A/4A/5A family of control ICs is a pin-for-pin compatible improved version of the UC3842/3/4/5 family. Providing the necessary features to control current-mode switched-mode power supplies this device has been improved for higher frequency off-line power supplies. This new A series of controllers UC1842A/43A/44A/45A is superior to its predecessors in startup current requirements
  • DN-26 UC3842A Low-Cost Start-up and Fault Protection Circuit
    PDF, 155 Kb, Datei veröffentlicht: Sep 5, 1999
    The UC1842/3/4/5 family of control ICs can implement off-line or DC-to-DC fixed-frequency current-mode control schemes with a minimal external parts count. This design note describes a circuit with low startup current (less than 0.5mA) MOSFET-compatible undervoltage lockout thresholds programmable restart-delay HICCUP fault protection auxiliary 5V precision reference and overvoltage/overtemper
  • DN-65 Considerations in Powering BiCMOS ICs
    PDF, 100 Kb, Datei veröffentlicht: Sep 5, 1999
    Bipolar linear integrated circuits have been with us for years in the form of PWM and PFC controllers supervisory circuits and other circuits. Since these devices have traditionally used relatively high-voltage (35V) bipolar processes powering was not a concern. In addition many of these ICs contained high-current protection zeners to keep higher voltages from damaging the devices. With a numb
  • Understanding Boost Power Stages In Switchmode Power Supplies
    PDF, 149 Kb, Datei veröffentlicht: Mar 4, 1999
    A switching power supply consists of the power stage and the control circuit. The power stage performs the basic power conversion from the input voltage to the output voltage and includes switches and the output filter. This report addresses the boost power stage only and does not cover control circuits. The report includes detailed steady-stage and small-signal analysis of the boost power stage o
  • UCC38C42 Family of High-Speed BiCMOS Current-Mode PWM Controllers
    PDF, 280 Kb, Datei veröffentlicht: Feb 7, 2002
    Since their introduction in the mid 1980?s the bipolar UC3842 family of Pulse width modulation (PWM)controllers has grown to become the most widely-used control strategy in the power supply industry. [1] The reasons for success are quite clear the devices feature an elegantly simple yet very effective control architecture they use only 8 pins they can drive MOSFET gates directly and they offer
  • U-111 Practical Considerations in Current Mode Power Supplies
    PDF, 787 Kb, Datei veröffentlicht: Sep 5, 1999
    This application note explains the numerous PWM functions and ways to maximize their usefulness. It covers practical circuit design considerations such as slope compensation gate drive circuitry external control functions synchronization and paralleling current-mode controlled modules. Circuit diagrams and simplified equations are included.
  • DN-42A Design Considerations for Transitioning from UC3842 to the New UCC3802
    PDF, 42 Kb, Datei veröffentlicht: Sep 5, 1999
    The UCC3802 offers numerous advantages that allow the power supply design engineer to meet requirements for lower power for battery-operated equipment higher switching frequencies for reduced magnetics size higher levels of circuit integration for improved reliability and lower cost. The UCC3802 family of devices is pin-out compatible with the UC3842 and UC3842A families; however it is not plu
  • Conditioning a Switch-mode Power Supply Current Signal Using TI Op Amps
    PDF, 61 Kb, Datei veröffentlicht: Mar 23, 2000
    The switch-mode power supply primary current is often sensed using a power resistor. Using an op amp to amplify the current-sense signal can reduce cost and improve noise performance and efficiency. This report reviews the advantages of using an op amp circuit and analyzes the design criteria needed to choose the proper op amp.
  • Understanding Buck-Boost Power Stages in Switchmode Power Supplies (Rev. A)
    PDF, 363 Kb, Revision: A, Datei veröffentlicht: May 28, 2002

Modellreihe

Herstellerklassifikation

  • Semiconductors > Power Management > Offline and Isolated DC/DC Controllers and Converters > PWM and Resonant Controller