Sharp LC-24DV250K (serv.man2) Service Manual ▷ View online
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LC-24DV250 (C)
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TPS65251 features a supervisor circuit that monitors each converter output. The PGOOD
pin is asserted once sequencing is done, all PG signals are reported and a selectable end of
reset time lapses. The polarity of the PGOOD signal is active high.
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
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LC-24DV250 (C)
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Table 5: Recommended operating conditions
Figure 7: Pin description
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LC-24DV250 (C)
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Table 6: Pin functions
MP1484
a)
General Description
The MP1484 is a monolithic synchronous buck regulator. The device integrates top and
bottom 85m
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 1
A.
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 85m
Power MOSFET Switches
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LC-24DV250 (C)
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