Offering cable interface protection to ±60 V, Linear Tech’s LT3669/-2 IO-Link PHY-compatible (COM1/COM2/COM3) transceivers with step-down regulator and low-dropout linear regulator (LDO) operate within a 7.5 to 40 V input range, suiting them for industrial sensor applications. System reliability gets a boost from wakeup detect functionality and a programmable power-on reset timer. The LT3669’s internal switching regulator delivers up to 100 mA of load current, while the LT3669-2 extends to 300 mA. Both offer high efficiency at 0.8- to 16-V output voltages. The LDO, powered from the switcher output, provides an additional output for more flexibility. Constant-frequency/synchronizable operation includes programmable switching frequencies between 250 kHz and 2.2 MHz, enabling the use of tiny externals. Rugged line drivers with adjustable slew rates and current limit are externally adjustable to optimize electromagnetic compatibility. They can source/sink up to 250 mA of current each, or 500 mA when connected together. An adaptive line-driver pulsing scheme safely switches heavy loads. Both transceivers come in 28-pin, thermally enhanced, 4- by 5-m QFN packages.