IO-Link Transceiver Integrates Step-Down Regulator, LDO

The LT3669 from Linear Technology  is an IO-Link PHY compatible (COM1/COM2/COM3) industrial transceiver that includes a high efficiency step-down regulator and a low dropout linear regulator. The device offers cable interface protection to ±60 V. Wake-up detect functionality as well as a programmable power-on reset timer are included for system reliability. The LT3669/-2 operates from a 7.5 V to 40 V input voltage range, making it ideal for industrial sensor applications. The LT3669’s internal switching regulator can deliver up to 100 mA of load current, whereas the LT3669-2 delivers up to 300 mA. Both versions can deliver high efficiency at output voltages from 0.8 V to 16 V. The integrated LDO, powered from the switcher output, provides an additional output to offer additional design flexibility while maintaining high efficiency. Both versions feature constant frequency/synchronizable operation with programmable switching frequencies between 250 kHz and 2.2 MHz. This enables the use of tiny externals, which combined with the 4 mm x 5 mm QFN-28, offer a highly compact solution footprint for industrial IO-Link sensor applications.

The LT3669/-2 feature rugged line drivers with adjustable slew rates and current limit which are externally adjustable to optimize EMC performance. The line drivers can source/sink up to 250 mA of current each or 500 mA when connected together, with a minimal residual voltage of less than 2.1 V. An adaptive line driver pulsing scheme safely switches heavy loads. The drivers are easily configurable as push-pull, pull-up or pull-down to maximize system flexibility. Other features include current limit detection and thermal shutdown. The LT3669EUFD and LT3669EUFD-2 are both available from stock in a 28-Pin thermally enhanced 4mm x 5mm QFN package. 1,000 piece pricing starts at $3.55 each. Industrial grade versions, the LT3669IUFD and LT3669IUFD-2, are guaranteed to operate over the -40 °C to +125 °C operating junction temperature range and the high temperature grade versions, the LT3669HUFD and LT3669HUFD-2 are guaranteed to operate over the -40 °C to +150 °C. All versions are available from stock.