TPS51222
www.ti.com. SLUS908 – JANUARY 2009 Fixed Frequency, 99% Duty Cycle Peak Current Mode Notebook System Power Controller
FEATURES 1 Input Voltage Range: 4.5 V to 32 V Output Voltage Range: 1 V to 12 V Selectable Light Load Operation
(Continuous / Auto Skip / Out-Of-Audioв„ў Skip) Programmable Droop Compensation Voltage Servo Adjustable Soft Start 200-kHz to 1-MHz Fixed-Frequency PWM Current Mode Architecture 180В° Phase Shift Between Channels Resistor or Inductor DCR Current Sensing Current Monitor Output for Each Channel Adaptive Zero Crossing Circuit Powergood Output for Each Channel OCL/OVP/UVP/UVLO Protections Thermal Shutdown (Non-Latch) Output Discharge Function Integrated Boot Strap MOSFET Switch QFN-32 (RTV) Package APPLICATIONS 2 Notebook Computer System and I/O Bus
Point of Load in LCD TV, MFP DESCRIPTION
The TPS51222 is a dual synchronous buck regulator
controller with two 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 TPS51222 supports high
efficiency, fast transient response, and 99% duty
cycle operation. It supports supply input voltage
ranging from 4.5 V to 32 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 cycle (99%) operation and
the 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 1 MHz by a resistor, and
each channel runs 180В° out-of-phase. The TPS51222
can also synchronize to the external clock, and the
interleaving ratio can be adjusted by its duty. The …
