The PTN78000A is a series of high-efficiency, buck-boost integrated switching regulators (ISR), that represent the third generation in the evolution of the PT78NR100 series of products. In new designs, it should be considered in place of the PT78NR100 series of single in-line pin (SIP) products. The PTN78000A is smaller and lighter than its predecessor, and has either similar or improved electrical performance characteristics. The caseless, double-sided package also exhibits improved thermal characteristics, and is compatible with TI's roadmap for RoHS and lead-free compliance. Operating from a wide-input voltage range, the PTN78000A provides high-efficiency, positive-to-negative voltage conversion for loads of up to 1.5 A. The output voltage is set using a single external resistor, and may be set to any value within the range, 15 V to 3 V. The PTN78000A has undervoltage lockout, and is suited to a wide variety of general-purpose applications that operate off 12-V, 24-V, or tightly regulated 28-V dc power.