features
DC-DC Synchronous Buck Controller
Switching Frequency, 200 kHz (Typ)
Programmable Output Voltage,
1 V to 2.5 V ±2%
Power Good Function (PWRGD)
Input Voltage, 12 V ±5%
Drive High Load Current With External
Components

description
The TPPM0115 is a synchronous buck controller capable of driving two external power FETs 180° out of phase.
The device requires a minimum of external standard filter components and switching FETs to regulate the
desired output voltage. This is achieved with an internal switching frequency of 200 kHz (typical).
The TPPM0115 switch mode controller and associated circuitry provide efficient voltage regulation of greater
than 85%. The output voltage is set by two external resistors. During power up, when the output voltage reaches
90% of the desired value, the power good (PWRGD) output is transitioned high after a short delay of 1 ms to
5 ms. During power down, when the output voltage falls below 90% of the set value, the PWRGD output is pulled
low without any delay.
In the event the set output is in an over-voltage condition due to a system fault, the drive to the lower FET turns
on to correct the fault. There is a dead time between switching one FET ON while the other FET is switching
OFF to prevent cross conduction.
The TPPM0115 is capable of driving high static load currents with minimal ripple on the output (<2%). The phase
sense input is used to sense the flow of current through the inductor during flyback to minimize ripple on the
output.
To optimize output filter capacitance, the voltage mode control is based on a fixed ON time during the start of
the cycle and hysteretic control during load transients. This allows the device to respond and maintain the set
regulation voltage.
applications
PC Motherboard, Voltage Regulation for
System Power
DDR Memory Supply (VDDQ or VTT)
RDRAM Memory Supply (VDDQ)
General Purpose Synchronous Switch
Mode Controller