The MC34025 series are high speed, fixed frequency, double−ended pulse width modulator controllers optimized for high frequency operation. They are specifically designed for Off−Line and DC−to−DC converter applications offering the designer a cost effective solution with minimal external components. These integrated circuits feature an oscillator, a temperature compensated reference, a wide bandwidth error amplifier, a high speed current sensing comparator, steering flip−flop, and dual high current totem pole outputs ideally suited for driving power MOSFETs.
Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cycle−by−cycle current limiting, and a latch for single pulse metering.
The flexibility of this series allows it to be easily configured for either current mode or voltage mode control.
Features
• 50 ns Propagation Delay to Outputs
• Dual High Current Totem Pole Outputs
• Wide Bandwidth Error Amplifier
• Fully−Latched Logic with Double Pulse Suppression
• Latching PWM for Cycle−By−Cycle Current Limiting
• Soft−Start Control with Latched Overcurrent Reset
• Input Undervoltage Lockout with Hysteresis
• Low Startup Current (500 A Typ)
• Internally Trimmed Reference with Undervoltage Lockout
• 45% Maximum Duty Cycle (Externally Adjustable)
• Precision Trimmed Oscillator
• Voltage or Current Mode Operation to 1.0 MHz
• Functionally Similar to the UC3825
• Pb−Free Packages are Available*
Click to view :
MC34025.pdf
