UCC28221

具有可编程最大占空比的双路交错 PWM 控制器

The UCC28220 and are a family of BiCMOS interleaved dual channel PWM controllers. Peak current mode control is used to ensure current sharing between the two channels. A precise maximum duty cycle clamp can be set to any value between 60% and 90% duty cycle per channel.

The UCC28220 has an UVLO turnon threshold of 10 V for use in 12-V supplies while UCC28221 has a turnon threshold of 13 V for systems needing wider UVLO hysteresis. Both have 8-V turnoff thresholds.

Additional features include a programmable internal slope compensation with a special circuit which is used to ensure exactly the same slope is added to each channel and a high-voltage 110-V internal JFET for easier start-up for the wider hysteresis UCC28221 version.

The UCC28220 is available in both 16-pin SOIC and low-profile TSSOP packages. The UCC28221 also comes in 16-pin SOIC package and a slightly larger 20-pin TSSOP package to allow for high-voltage pin spacing to meet UL1950 creepage clearance safety requirements.

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2-MHz High-Frequency Oscillator With 1-MHz Operation Per Channel

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Matched Internal Slope Compensation Circuits

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Programmable Maximum Duty Cycle Clamp 60% to 90% Per Channel

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Peak Current Mode Control With Cycle-by-Cycle Current Limit

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Current Sense Discharge Transistor for Improved Noise Immunity

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Accurate Line Undervoltage and Overvoltage Sense With Programmable Hysteresis

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Opto-Coupler Interface

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110-V Internal Start-Up JFET UCC28221

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Operates From 12-V Supply UCC28220

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Programmable Soft Start