Sharp LC-42LE761K Service Manual ▷ View online
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LC-42/50LE762
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TPS65251 also features a light load pulse skipping mode (PSM) by allowing the LOW_P
pin tied to V3V. The PSM mode allows for a reduction on the input power supplied to the
system when the host processor is in stand-by (low activity) mode.
b) Features
• Wide Input Supply Voltage Range (4.5 V - 18 V)
• 0.8 V, 1% Accuracy Reference
• Continuous Loading: 3 A (Buck 1), 2 A (Buck 2 and 3)
• Maximum Current: 3.5 A (Buck 1), 2.5 A (Buck 2 and 3)
• Adjustable Switching Frequency 300 kHz - 2.2 MHz Set By External Resistor
• Dedicated Enable for Each Buck
• External Synchronization Pin for Oscillator
• External Enable/Sequencing and Soft Start Pins
• Adjustable Current Limit Set By External Resistor
• Soft Start Pins
• Current-Mode Control With Simple Compensation Circuit
• Power Good
• Optional Low Power Mode Operation for Light Loads
• QFN Package, 40-Pin 6 mm x 6 mm RHA
APPLICATIONS
• Set Top Boxes
• Blu-ray DVD
• Security Camera
• Car Audio/Video
• DTV
• DVR
Table: Recommended operating conditions
Figure: Pin Description
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Table: Pin functions.
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MP1484
a) General Description
The MP1484 is a monolithic synchronous buck regulator. The device integrates top and bottom 85mΩ
MOSFETS that provide 3A of continuous load current over a wide operating input voltage of 4.75V to
18V. Current mode control provides fast transient response and cycle-by-cycle current limit.
An adjustable soft-start prevents inrush current at turn-on and in shutdown mode, the supply current
drops below 1μA. The MP1484 is PIN compatible to the MP1482 2A/18V/Synchronous Step-Down
Converter.
b) Features
• 3A Continuous Output Current
• Wide 4.75V to 18V Operating Input Range
• Integrated 85mΩ Power MOSFET Switches
• Output Adjustable from 0.925V to 20V
• Up to 95% Efficiency
• Programmable Soft-Start
• Stable with Low ESR Ceramic Output Capacitors
• Fixed 340KHz Frequency
• Cycle-by-Cycle Over Current Protection
• Input Under Voltage Lockout
• Thermally Enhanced 8-Pin SOIC Package
APPLICATIONS
• FPGA, ASIC, DSP Power Supplies
• LCD TV
• Green Electronics/Appliances
• Notebook Computers
Figure: General description
Figure: General description
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Table: Pin functions.
APL5910
a) General Description
The APL5910 is a 1A ultra low dropout linear regulator. The IC needs two supply voltages, one is a
control voltage (VCNTL) for the control circuitry, the other is a main supply voltage (VIN) for power
conversion, to reduce power dissipation and provide extremely low dropout voltage. The APL5910
integrates many functions. A Power-On-Reset (POR) circuit monitors both supply voltages on VCNTL
and VIN pins to prevent erroneous operations. The functions of thermal shutdown and current-limit protect
the device against thermal and current over-loads. A POK indicates that the output voltage status with a
delay time set internally. It can control other converter for power sequence. The APL5910 can be enabled
by other power systems. Pulling and holding the EN voltage below 0.4V shuts off the output.
The APL5910 is available in a SOP-8P package which features small size as SOP-8 and an Exposed
Pad to reduce the junction-to-case resistance to extend power range of applications.
b) Features
Ultra Low Dropout
-0.12V (Typical) at 1AOutput Current
0.8V Reference Voltage
High Output Accuracy
-±1.5%over Line, Load, and Temperature Range
Fast Transient Response
Adjustable Output Voltage
Power-On-Reset Monitoring on Both VCNTL and VIN Pins
Internal Soft-Start
Current-Limit and ShortCurrent-Limit Protections
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