UC3844A

电流模式 PWM 控制器

The UCx84xA family of control ICs is a pin-for-pin compatible improved version of the UCx84x family. Providing the necessary features to control current-mode or switched-mode power supplies, this family of devices has many improved features: startup current is less than 0.5 mA, oscillator discharge is trimmed to 8.3 mA, and during UVLO, the output stage can sink at least 10 mA at less than 1.2 V for VCC over 5 V.

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Optimized for Off-Line and DC-DC Converters

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Low Start-Up Current < 0.5 mA

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Trimmed Oscillator Discharge Current

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Automatic Feedforward Compensation

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Pulse-by-Pulse Current Limiting

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Enhanced Load Response Characteristics

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Undervoltage Lockout With Hysteresis

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Double Pulse Suppression

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High-Current Totem Pole Output

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Internally-Trimmed Bandgap Reference

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Up to 500-kHz Operation