For lower current rails, the ISL85410 and ISL85418 are integrated synchronous buck regulators that work directly off the high voltage rail thanks to a wide input voltage range of 3V to 40V. They have integrated MOSFETs (RDS(ON) of 250/90mΩ), a bootstrap diode, and internal compensation for a compact solution size. The switching frequency is adjustable from 300kHz to 2MHz and can be synchronized with an external clock. Features include adjustable soft-start, enable, power good, and full protection, including over current, over and under voltage, under voltage lockout, and temperature. The ISL85415 has an input voltage range of 3V to 36V and RDS(ON) of 450/250mΩ, but otherwise has the same features as the other two devices. These devices provide simplicity and reliability for mid to low current rails at high voltages. The adjustable features also allow for some design flexibility.