TPS92640PWPR

The TPS92640 and TPS92641 devices are high-voltage, synchronous N-channel field-effect transistor (NFET) controllers for step-down current regulators. Output current regulation is based on valley current mode operation with an on-time controlled architecture. This control method simplifies the loop compensation design while maintaining the switching frequency at an approximately constant level. The TPS92640 and TPS92641 devices contain a high-voltage start-up regulator that operates over a wide input range of 7V to 85V. The PWM controller is designed for high-speed performance with an oscillator frequency range up to 1MHz. Dead-time between high-side and low-side gate drivers is optimized for efficient operation over a wide input operating voltage and output power range. The TPS92640 and TPS92641 are capable of accepting both analog and PWM input signals, thus providing excellent dimming control range. Linear response characteristics between input command and LED current can be achieved by using a low offset error amplifier and dedicated PWM dimming logic to achieve true zero LED current. Both devices are also capable of providing precision reference currents for low-power microcontrollers. Protection features include: cycle-by-cycle current protection, overvoltage protection, and thermal shutdown. The TPS92641 device contains a shunt FET dimming input and MOSFET driver for high-resolution PWM dimming.