TI TPPM0115D

TPPM0115 is a synchronous buck controller capable of driving two external power FETs with phases 180° apart. The device requires only minimal external standard filter components and switching FETs to regulate the desired output voltage. This is achieved through an internal switching frequency of 200kHz (typical).

The TPPM0115 switch-mode controller and associated circuitry provide high-efficiency voltage regulation with efficiency exceeding 85%. The output voltage is set by two external resistors. At power-up, when the output voltage reaches 90% of the desired value, the Power Good (PWRGD) output goes high after a short delay of 1ms to 5ms. At power-down, when the output voltage falls below 90% of the set value, the PWRGD output is immediately pulled low.

If the set output enters an overvoltage condition due to a system fault, the low-side FET driver will turn on to correct the fault. Dead time exists during the switching transition when one FET turns on and the other turns off to prevent shoot-through.

The TPPM0115 is capable of driving high quiescent load currents with minimal output ripple (<2%). The phase sense input is used to sense the current through the inductor during the flyback period to minimize output ripple.

To optimize the output filter capacitor, voltage-mode control is based on a fixed on-time at the beginning of each cycle and hysteretic control during load transients. This enables the device to respond to and maintain the set regulation voltage.

• DC-DC synchronous buck controller
• Switching frequency 200kHz (typical)
• Programmable output voltage 1V to 2.5V, ±2%
• Power good function (PWRGD)
• Input voltage 12V, ±5%
• High load current capability via external components

• Computer motherboards, system power supply voltage regulation
• DDR memory supply (VDDQ or VTT)
• RDRAM memory supply (VDDQ)
• General-purpose synchronous switch-mode controller