TI TPS40192DRCT

TPS40192 and TPS40193 are cost-optimized synchronous buck controllers with an input operating voltage range of 4.5V to 18V. These controllers employ a voltage-mode control architecture with a fixed switching frequency of 600kHz (TPS40192) or 300kHz (TPS40193). The higher switching frequency enables the use of smaller inductors and output capacitors, facilitating a compact power supply solution. An adaptive anti-shoot-through scheme prevents shoot-through current in the power FETs.

Short-circuit detection is implemented by sensing the voltage drop across the low-side MOSFET (when conducting) and comparing it against a user-selectable threshold of 100mV, 200mV, or 280mV. This threshold is set via a single external resistor connected from COMP to GND. The resistor is sensed at startup and the selected threshold is latched. Cycle-by-cycle current limiting (to prevent current runaway) is provided by sensing the voltage across the high-side MOSFET (when conducting) and terminating the cycle when the voltage drop exceeds a fixed threshold of 550mV. If the controller detects an output short circuit, it shuts down both MOSFETs and attempts to restart after a timeout period. Under sustained fault conditions, this behavior enables limited power dissipation.

The TPS40192 and TPS40193 devices are cost optimized controllers providing all the necessary features to construct a high performance DC/DC converter while keeping costs to a minimum. Support for pre-biased outputs eliminates concerns about damaging sensitive loads during startup. Strong gate drivers for the high-side and rectifier N-channel MOSFETs decrease switching losses for increased efficiency. Adaptive gate drive timing prevents shoot through and minimizes body diode conduction in the rectifier MOSFET, also increasing efficiency. Selectable short circuit protection thresholds and hiccup recovery from a short circuit increase design flexibility and minimize power dissipation in the event of a prolonged output fault. The dedicated ENABLE pin allows the converter to be placed in a very low quiescent current shutdown mode. Internally fixed switching frequency and soft-start time reduce external component count, simplifying design and layout, as well as reducing footprint and cost. The 3-mm×3-mm package size also contributes to a reduced overall converter footprint.

• Input operating voltage range: 4.5V to 18V
• Output current up to 20A
• Pre-biased output supported
• 0.5%, 591mV reference
• Switching frequency: TPS40192: 600kHz, TPS40193: 300kHz
• Three selectable temperature-compensated short-circuit protection levels
• Hiccup restart under fault conditions
• Internal 5V regulator
• High-side and low-side MOSFET RDS(on) current sensing
• 10-pin 3mm×3mm SON package
• Internal 4ms soft-start time
• Thermal shutdown at 145°C

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