April 3, 2014 – Linear Technology Korea (CEO Hong Sa-kwak) announced the launch of a high-efficiency secondary-side MOSFET driver (Product Name: LT8311). This product operates in isolated forward converters without being controlled from the primary side. The LT8311's proprietary preactive mode detects signals on the secondary side to control synchronous rectification, eliminating the need for a signal transformer for primary-to-secondary communication. This mode reduces the number of components and the size of the solution.

The LT8311 operates over an input voltage range of 3.7V to 30V and is used in conjunction with the primary IC LT3752/-1. The integrated forward converter operates over input voltages ranging from 6.5V to 400V+, making it ideal for a wide range of applications, including hybrid and electric vehicle requirements. Furthermore, the LT8311 integrates a 10mA opto driver and a feedback loop error amplifier to enable output voltage feedback from the secondary side to the primary side. The entire system provides fixed-frequency peak current mode control with excellent line/load regulation and high-speed transient response capabilities. Additional features include a 1.5% reference voltage, power good monitor, and a programmable soft-start function for the output voltage.

The LT8311 is supplied in a TSSOP-20 package with several pins removed to provide adequate clearance for high peak voltages. The LT8311 E- and I- rated versions operate at junction temperatures of -40°C to 125°C. The LT8311 H rated version guarantees operation at junction temperatures of -40°C to 150°C. The LT8311 MP rated version guarantees operation at junction temperatures of -55°C to 150°C.

Photo Caption: Synchronous Forward MOSFET Driver