SEA05 Datasheet, PDF (1/10 Pages) STMicroelectronics – Advanced constant voltage and constant current controller

SEA05
Advanced constant voltage and constant current controller
Features
■ Constant voltage and constant current control
■ Wide operating V_CC range [3.5 - 36] V
■ Low quiescent consumption: 200 µA
■ Voltage reference: 2.5 V
■ Voltage control loop accuracy +/- 0.5%
■ Current sense threshold: 50 mV
■ Open-drain output stage
■ Low external component count
■ SOT23-6L micro package
Applications
■ Battery chargers
■ AC-DC adapters
■ LED drivers
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
SOT23 - 6L
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
Vcc
2.5 V
6
1.23 V
+
-
5 Out
3 Vctrl
+
-
2 Gnd
4
1
Ictrl
Isense
Table 1. Device summary
Order code
Package
SEA05TR
SOT23-6L
Packing
Tape and reel
April 2010
Doc ID 17014 Rev 1
1/10
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