描述 The TPS51216 provides a complete power supply for DDR2, DDR3 and DDR3L memory systems in the lowest total cost and minimum space. It integrates a synchronous buck regulator controller (VDDQ) with a 2-A sink/source tracking LDO (VTT) and buffered low noise reference (VTTREF). The TPS51216 employs D-CAP™ mode coupled with 300 kHz/400 kHz frequencies for ease-of-use and fast transient response. The VTTREF tracks VDDQ/2 within excellent 0.8% accuracy. The VTT, which provides 2-A sink/source peak current capabilities, requires only 10-μF of ceramic capacitance. In addition, adedicated LDO supply input is available.The TPS51216 provides rich useful functions as well as excellent power supply performance. It supports flexible power state control, placing VTT at high-Z in S3 and discharging VDDQ, VTT and VTTREF (soft-off) in S4/S5 state. Programmable OCL with low-side MOSFET RDS(on) sensing, OVP/UVP/UVLO and thermal shutdown protections are also available.The TPS51216 is available in a 20-pin, 3 mm × 3 mm, QFN package and is specified for ambient temperature from –40°C to 85°C.特性 Synchronous Buck Controller (VDDQ)Conversion Voltage Range: 3 V to 28 V Output Voltage Range: 0.7 V to 1.8 V 0.8% VREF Accuracy D-CAP™ Mode for Fast Transient Response Selectable 300 kHz/400 kHz Switching Frequencies Optimized Efficiency at Light and Heavy Loads with Auto-skip Function Supports Soft-Off in S4/S5 States OCL/OVP/UVP/UVLO Protections Powergood Output 2-A LDO(VTT), Buffered Reference(VTTREF)2-A (Peak) Sink and Source Current Requires Only 10-μF of Ceramic Output Capacitance Buffered, Low Noise, 10-mA VTTREF Output 0.8% VTTREF, 20-mV VTT Accuracy Support High-Z in S3 and Soft-Off in S4/S5Thermal Shutdown 20-Pin,3 mm × 3 mm,QFN PackageAPPLICATIONSDDR2/DDR3/DDR3L Memory Power Supplies SSTL_18, SSTL_15, SSTL_135 and HSTL Termination