Mp2012 (U176); General Description; Features; Pinning - Sharp LC-22LE240E Service Manual

13. MP2012 (U176)

13.1. General Description

The MP2012 is a fully integrated, internally compensated 1.2MHz fixed frequency PWM
step-down converter. It is ideal for powering portable equipment that runs from a single
cell Lithium-Ion (Li+) Battery, with an input range from 2.7V to 6V. The MP2012 can
provide up to 1.5A of load current with output voltage as low as 0.8V. It can also operate
at 100% duty cycle for low dropout applications. With peak current mode control and
internal compensation, the MP2012 is stable with ceramic capacitors and small inductors.
Fault condition protection includes cycle-by-cycle current limiting and thermal shutdown.

13.2. Features

 2.7-6V Input Operation Range
 Output Adjustable from 0.8V to VIN
 1μA Max Shutdown Current.
 Up to 95% Efficiency
 100% Duty Cycle for Low Dropout
 Applications
 1.2MHz Fixed Switching Frequency
 Stable with Low ESR Output Ceramic
 Capacitors
 Thermal Shutdown
 Cycle-by-Cycle Over Current Protection
 Short Circuit Protection
 Available in 6-pin 3x3mm QFN

13.3. Pinning

Pin Name
#
1 FB
2 GND,
Exposed
Pad
3 SW
4 PVIN
5 VIN
6 EN
14. RTA8283A (U23, U173)
Description
Feedback input. An external resistor divider from
the output to GND, tapped to the FB pin sets the
output voltage.
Ground pin. Connect exposed pad to ground
plane for proper thermal performance.
Switch node to the inductor.
Input supply pin for power FET.
Input Supply pin for controller. Put small
decoupling ceramic near this pin.
Enable input, "High" enables MP2012. EN is
pulled to GND with 1Meg internal resistor.
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LC-22LE240