Smooth transition between step-down and step- up modes
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Switching frequency programmable to 500KHz
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Oscillator synchronization capability
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Internal high voltage bias regulator
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Integrated high and low-side gate drivers
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Programmable soft-start time
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Ultra low shutdown current
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Enable input wide bandwidth error amplifier
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1.5% feedback reference accuracy
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Thermal shutdown
General Description
The LM5118 wide voltage range Buck-Boost switching regulator controller features all of the functions necessary to implement
a high performance, cost efficient Buck-Boost regulator using a minimum of external components. More...
The LM5118 wide voltage range Buck-Boost switching regulator controller features all of the functions necessary to implement
a high performance, cost efficient Buck-Boost regulator using a minimum of external components. The Buck-Boost topology maintains
output voltage regulation when the input voltage is either less than or greater than the output voltage making it especially
suitable for automotive applications. The LM5118 operates as a buck regulator while the input voltage is sufficiently greater
than the regulated output voltage and gradually transitions to the buck-boost mode as the input voltage approaches the output.
This dual mode approach maintains regulation over a wide range of input voltages with optimal conversion efficiency in the
buck mode and a glitch-free output during mode transitions. This easy to use controller includes drivers for the high side
buck MOSFET and the low side boost MOSFET. The regulator’s control method is based upon current mode control utilizing an
emulated current ramp. Emulated current mode control reduces noise sensitivity of the pulse-width modulation circuit, allowing
reliable control of the very small duty cycles necessary in high input voltage applications. Additional protection features
include current limit, thermal shutdown and an enable input. The device is available in a power enhanced TSSOP-20 package
featuring an exposed die attach pad to aid thermal dissipation.
RoHS Compliance Information
