The TPS51120 is a highly sophisticated dual, synchronous step-down controller. It is a
full featured controller designed to run directly off a three- or four-cell Li-ion battery and
provide high-power and 5-V and/or 3.3-V standby regulation for all the downstream circuitry in a
notebook computer system. High-current, 100-mA, 5-V or 3.3-V on-board linear regulators have
glitch-free switch over function to SMPS and can be kept alive independently during standby state.
The pseudo-constant frequency adaptive on-time control scheme supports full range of current mode
operation including simplified loop compensation, ceramic output capacitors as well as seamless
transition to reduced frequency operation at light-load condition. Optional D-CAP mode operation
optimized for SP-CAP or POSCAP output capacitors allows further reduction of external compensation
parts. Dynamic UVP supports VIN line sag without latch off by hitting 5-V UVP. No negative voltage
appears at output voltage node during UVLO, UVP, and OCP, OTP or loss of VIN.
The TPS51120 32-pin QFN package is specified from –40°C to 85°C ambient
temperature.
