IP7700 广闳

. Description

The iP7700 is a highly integrated solution for

SMPS ( Switching Mode Power Supply ) applications re a dual control loop to perform CV ( constant voltage, current limit for Power Supply application) and CC (constant current, voltage limit for LED Driver application ).

The iP7700 integrates a voltage reference, two op amps ( with OR-ed open-drain outputs ), and a low-side current sensing circuit.

The voltage reference, along with one op amp, is the core of the voltage control loop; the current sensing circuit and the other op amp make up the current control loop.

The external components needed to complete the

two control loops are:

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A resistor divider that senses the output of the power supply ( adapter, battery charger ) and fixes the voltage regulation set point at the specified value;

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A sense resistor that feeds the current sensing circuit with a voltage proportional to the dc output current; this resistor determines the current regulation set point and must be ade rated in terms of power dissipation;

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Frequency compensation components ( RC networks ) for both loops.

The iP7700, housed in one of the smallest package is ideal for space-shrunk applications such as adapters and chargers.

2.

Features

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Secondary-side constant voltage and constant current control

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Wide operation voltage 2.5-40 V

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Very low consumption

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High-accuracy internal reference

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Low external component count

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SOT23-6L micro package

3.

Applications

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Battery chargers

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AC / DC adapters

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LED lighting