The LT3669 from Linear Technology is an industrial transceiver that includes a step-down switching regulator and a low-dropout linear regulator. Wake-up detect functionality, as well as a programmable power-on reset timer are also included. The current-limit and slew-rate of the transmitters are externally adjustable for optimum 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 internal adaptive pulsing scheme allows the drivers to safely switch heavy-capacitive loads and incandescent bulbs. Thermal shutdown provides additional protection. Line protection of ±60 V in the line interface pins allows the use of standard TVS diodes with L+ operating voltages up to 40 V. The switching regulator integrates the catch diode in LT3669 (up to 100 mA load current) and requires an external catch diode in LT3669-2 (up to 300 mA load current). The LT3669 implements an IO-Link device PHY. For IO-link master designs, see the LTC2874.