HV300

The Supertex HV300 (and HV310), Hotswap Controller, Negative Supply control power supply connection during insertion of cards or modules into live backplanes. They may be used in traditional 'negative 48V' powered systems or for higher voltage busses up to negative 90V.

Operation during the initial power up prevents turn-on glitches, and after complete charging of load capacitors (typically found in filters at the input of DC-DC converters) the HV300 (and HV310) issues a power good signal. This signal is typically sed to enable the DC-DC converter.

The only difference between the HV300 and the HV310 is the polarity of the PWRGD signal line to accommodate different DC-DC converter models. Once PWRGD signal has been established the device sleeps in a low power state, important for large systems with many individual hotswap cards or modules.

An external power MOSFET is required as the pass element, plus a ramp capacitor, and resistors to establish current limiting and over and under voltage lockouts. There is no need for additional external snubber components.

Features are programmable over voltage and under voltage detection of the input voltage which locks out the load connection if the bus (input) voltage is out of range. An internal voltage regulator creates a stable reference, and maintains accurate gate drive voltage. The unique control loop scheme provides full current control and limiting during start up.