The MC34067/MC33067 are high performance zero voltage switch resonant mode controllers designed for off−line and dc−to−dc converter applications that utilize frequency modulated constant off−time or constant deadtime control. These integrated circuits feature a variable frequency oscillator, a precise retriggerable one−shot timer, temperature compensated reference, high gain wide bandwidth error amplifier, steering flip−flop, and dual high current totem pole outputs ideally suited for driving power MOSFETs.
Also included are protective features consisting of a high speed fault comparator and latch, programmable soft−start circuitry, input undervoltage lockout with selectable thresholds, and reference undervoltage lockout. These devices are available in dual−in−line and surface mount packages.
Features
• Zero Voltage Switch Resonant Mode Operation
• Variable Frequency Oscillator with a Control Range Exceeding 1000:1
• Precision One−Shot Timer for Controlled Off−Time
• Internally Trimmed Bandgap Reference
• 4.0 MHz Error Amplifier
• Dual High Current Totem Pole Outputs
• Selectable Undervoltage Lockout Thresholds with Hysteresis
• Enable Input
• Programmable Soft−Start Circuitry
• Low Startup Current for Off−Line Operation
• These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS Compliant
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MC34067DWG.PDF
