The TPS51221 is a dual synchronous buck regulator controller with 2 LDOs. It is optimized for 5-V/3.3-V system controller, enabling designers to cost effectively complete 2-cell to 4-cell notebook system power supply. The TPS51221 supports high efficiency, fast transient response and 99% duty cycle operation. It supports supply input voltage ranging from 4.5 V to 28 V, and output voltages from 1 V to 12 V. Peak current mode supports stability operation with lower ESR capacitor and output accuracy. The high duty (99%) operation and wide input/ output voltage range supports flexible design for small mobile PCs and a wide variety of other applications. The fixed frequency can be adjusted from 200 kHz to 1MHz by a resistor, and each channel runs 180° out of phase. The TPS51221 can also synchronize to the external clock, and the interleaving ratio can be adjusted by its duty. The TPS51221 is available in the 32-pin 5×5 QFN package and is specified from -40°C to 85°C.

• Input Voltage Range: 4.5 V to 28 V
• Output Voltage Range: 1 V to 12 V
• Selectable Light Load Operation (Continuous / Auto Skip / Out-Of-Audio™ Skip)
• Programmable Droop Compensation
• Voltage Servo Adjustable Soft Start
• 200 kHz to 1 MHz Fixed Frequency PWM
• Current Mode Architecture
• 180° Phase Shift Between Channels
• Resistor or Inductor DCR Current Sensing
• Powergood Output for each channel
• OCL/OVP/UVP/UVLO protections
• Current Monitor Output for CH1
• Thermal Shutdown (Non-latch)
• Output Discharge Function (Disable option)
• Integrated Boot Strap MOSFET Switch
• QFN32 (RTV)
• APPLICATIONS
  • Notebook Computer System and I/O Bus
  • Point of load in LCD TV, MFP

Out-Of-Audio, PowerPAD are trademarks of Texas Instruments.