Operating from a 7.5-40V input voltage range suitable for industrial sensor applications, the LT3669 is an IO-Link PHY compatible (COM1/COM2/COM3) industrial transceiver from Linear Technology. The device includes an integrated high efficiency step-down regulator and a low dropout (LDO) linear regulator.
The LT3669/LT3669-2 features cable interface protection to ±60V, wake-up detect functionality and a programmable power-on reset timer for system reliability. The integrated LDO is powered from the switcher output, providing an additional output to increase design flexibility while maintaining high efficiency.
The LT3669 has an internal switching regulator which can deliver up to 100mA of load current, whereas the LT3669-2 delivers up to 300mA. Both versions can deliver high efficiency at output voltages of 0.8-16V and feature constant frequency/synchronisable operation with programmable switching frequencies between 250kHz and 2.2MHz, enabling tiny external components to be used. Combined with the 4x5mm QFN-28 package of the LT3669, this provides a highly compact solution footprint for industrial IO-Link sensor applications.
The LT3669’s rugged line drivers with adjustable slew rates and current limit are externally adjustable to optimise EMC performance. With a minimal residual voltage of less than 2.1V, these line drivers can each source/sink up to 250mA of current. When connected together, they can source/sink up to 500mA. The drivers can be easily configured as push-pull, pull-up or pull-down to maximise system flexibility, while an adaptive line driver pulsing scheme safely switches heavy loads.
The LT3669 and LT3669-2 are both available in a 28-pin thermally enhanced 4x5mm QFN package in standard, industrial grade and high temperature grade versions, priced from $3.55 (USD) each in 1,000 unit quantities.