PTN78000 Integrated Switching Regulator Texas Instruments PTN78000 Integrated Switching Regulator (ISR) operates from a wide input voltage range and provides high-efficiency, positive-to-negative voltage conversion for loads of up to 1.5A. The TI PTN78000 ISR features a wide output voltage adjust of -15V to -3V and high efficiency of up to 84%. The Texas Instruments PTN78000 ISR is a third-generation device that is smaller and lighter than its predecessor with similar or improved electrical performance characteristics.