Sharp LC-32LE140E, Service Manual

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LC-32LE140
12. LM1117(U175, U180, U181)
12.1. General Description
The LM1117 is a series of low dropout voltage regulators with a dropout of 1.2V at 800mA
of load current. It has the same pin-out as National Semiconductor’s industry standard
LM317. The LM1117 is available in an adjustable version, which can set the output
voltage from 1.25V to 13.8V with only two external resistors. In addition, it is also
available in five fixed voltages, 1.8V, 2.5V, 2.85V, 3.3V, and 5V. The LM1117 offers
current limiting and thermal shutdown. Its circuit includes a zener trimmed bandgap
reference to as-sure output voltage accuracy to within ±1%. The LM1117 series is
available in SOT- 223, TO-220, and TO-252 D- PAK packages. A minimum of 10μF
tantalum capacitor is required at the output to improve the transient response and
stability.
12.2. Features
 Available in 1.8V, 2.5V, 2.85V, 3.3V, 5V, and Adjustable Versions
 Space Saving SOT-223 Package
 Current Limiting and Thermal Protection
 Output Current 800mA
 Line Regulation 0.2% (Max)
 Load Regulation 0.4% (Max)
 Temperature Range
 LM1117 0°C to 125°C
 LM1117I -40°C to 125°C
12.3. Applications
 2.85V Model for SCSI-2 Active Termination
 Post Regulator for Switching DC/DC Converter
 High Efficiency Linear Regulators 15
 32” TFT TV Service Manual 10/01/2005
 Battery Charger
 Battery Powered Instrumentation
12.4. Absolute Maximum Ratings
12.5. Pinning
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