April 2010

Doc ID 17014 Rev 1

1/10

10

SEA05

Advanced constant voltage and constant current controller

Features

Applications

Description

The SEA05 is a highly integrated solution for

SMPS applications requiring a dual control loop to

perform CV (constant voltage) and CC (constant

current) regulation.

The device 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: a resistor divider that

senses the output of the power supply and fixes

the voltage regulation setpoint at the specified

value; a sense resistor that feeds the current

sensing circuit with a voltage proportional to the

dc output current; this resistor determines the

current regulation setpoint and must be

adequately rated in terms of power dissipation;

the frequency compensation components (R-C

networks) for both loops.

The device, housed in one of the smallest

available package, is ideal for space-shrunk

applications such as adapters and chargers.

Figure 1.

Internal schematic

Table 1.

Device summary

Order code

Package

Packing

SEA05TR

SOT23-6L

Tape and reel

 

SOT23 - 6L

+

-

+

-

1.23 V

2.5 V

1

4

5

3

2

6

Ictrl

Isense

Gnd

Vctrl

Out

Vcc

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