Switch controller monitors power supplies up to 1000V DC
To protect and monitor high voltage DC power supplies up to 1000V, the LTM9100 micromodule is an all-in-one Isolated Anyside switch controller from Linear Technology.
It can be used for high voltage supplies used in industrial, datacomms, avionic and medical applications that 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, says the company. The controller saves design time, certification effort and board area by integrating all the functionality, including isolated power and digital telemetry, in a compact BGA package.
A 5kV RMS galvanic isolation barrier 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. This, says the company, saves 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 to monitor energy and power of the high voltage bus.
The LTM9100 can be configured for high side, low side (ground return) and floating applications. In-rush current is minimised by soft-starting the load, and the supply is protected from over-load and short-circuits with a current-limited circuit breaker. It can control inrush current in hot-swappable cards, AC transformers, motor drives and inductive loads. Adjustable under-voltage and over-voltage lockout thresholds ensure that the load operates only when the input supply is in its valid range. An integrated DC/DC converter, including the transformer, powers the isolated switch control side.
Operating temperature range is -40 to +105 degree C. The LTM9100 is offered in a
22 x 9.0 x 5.16mm BGA package, with 14.6mm of creepage distance between the logic side and the isolated side.