Switch controller protects and monitors high-voltage DC power supplies

Linear Technology Corporation has introduced the LTM9100 µModule (micromodule), an all-in-one Isolated Anyside switch controller that protects and monitors high-voltage DC power supplies up to 1,000V. High-voltage supplies used in industrial, datacom, avionic and medical applications require a controlled turn-on, with isolation needed for control circuit protection, operator safety and breaking ground paths. Alternative relay-based or discrete solutions are bulky, complex, component-intensive and lack safety certifications. The innovative LTM9100 saves design time, certification effort and board area by wrapping all the needed functionality, including isolated power and digital telemetry, in a compact BGA package.

A 5kV_RMS galvanic isolation barrier inside the LTM9100 separates the digital interface from the switch controller, driving an external N-channel MOSFET or IGBT switch. To guarantee a robust isolation barrier, the controller is production-tested to 6kV_RMS and will be recognised by the component-level UL 1577 standard, saving months of certification time for the end equipment manufacturer. Isolated digital measurements of load current, bus voltage and temperature are accessed via the I²C/SMBus interface, enabling power and energy monitoring of the high voltage bus.

Due to its isolated nature, the LTM9100 is easily configured for high side, low side (ground return) and floating applications. Inrush current is minimised by soft-starting the load, and the supply is protected from overload and short-circuits with a current-limited circuit breaker. The LTM9100 is versatile enough to control inrush current in hot-swappable cards, AC transformers, motor drives and inductive loads. Adjustable undervoltage and overvoltage lockout thresholds ensure that the load operates only when the input supply is in its valid range. A fully integrated DC/DC converter, including the transformer, powers the isolated switch control side.

Specified over the −40^oC to 105^oC temperature range, the LTM9100 is offered in a 22 x 9 x 5.16mm BGA package, with 14.6mm of creepage distance between the logic side and the isolated side. 1,000-piece pricing starts at $19.45 each. Device samples and evaluation circuit boards are available online or from your local Linear Technology sales office.