LM3075 High Efficiency, Synchronous Current Mode Buck Controller
September 2005
LM3075
High Efficiency, Synchronous Current Mode Buck
Controller
General Description
The LM3075 is a current mode control, synchronous buck
controller IC. Use of synchronous rectification and pulse-
skipping operation at light load achieves high efficiency over
a wide load range. Fixed frequency operation can be ob-
tained by disabling the pulse-skipping mode. Current mode
control assures excellent line and load regulation and a wide
loop bandwidth for fast response to load transients.
Current mode control can be achieved by either sensing
across the high side NFET or a sense resistor. The switching
frequency can be selected as either 200 kHz or 300 kHz
from an internal clock.
The LM3075 is available with an adjustable output in a
TSSOP-20 package.
Features
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Input voltage range of 4.5V-36V
Current Mode Control
Skip mode operation available
Cycle by cycle current limit
1.24V
鹵
2% Reference
Applications
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Automotive Power Supplies
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Distributed Power Systems
Typical Application Circuit
20162301
漏 2005 National Semiconductor Corporation
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