The LM25119 is a dual synchronous buck controller intended for step-down regulator applications from a highvoltageorwidelyvaryinginput supply.The control method is based upon current mode control utilizing an emulated current ramp.Current mode control provides inherent line feed-forward, cycle-by- cycle current limiting and easeof loop compensation. The use of an emulated control ramp reduces noise sensitivity of thepulse-width modulation circuit, allowing reliable control of very small duty cycles necessary inhigh input voltage applications. The switching frequency is programmable from 50 kHz to 750 kHz. The LM25119 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation forimproved efficiency at light load conditions. A high voltage bias regulator with automaticswitch-over to external bias furtherimprovesefficiency.Additionalfeatures include thermalshutdown, frequency synchronization, cycle-by-cycle and hiccup mode current limit and adjustableline under-voltage lockout. The device is available in a power enhanced leadless WQFN-32 packagefeaturing an exposed die attach pad to aid thermal dissipation.
LM25119Q is an Automotive Grade product that is AEC-Q100 grade 1 qualified (–40°C to 125°C operating junction temperature).
Emulated peak current mode control
Wide operating range from 4.5 V to 42 V
Easily configurable for dual outputs or interleaved single output