Hot-Plug Switch for 12V Backplane Applications

Maxim introduces the DS4560, a fully integrated, self-protected, resettable hot-plug switch. This device reduces the number of components required for the safe insertion and removal of systems on 12V powered backplanes. To minimize solution size and simplify design, the DS4560 integrates a 25mΩ n-channel power MOSFET, thus eliminating the need for an external MOSFET. Designed for use in 12V systems, the DS4560 is ideal for hot-swap applications such as enterprise-class hard drives, servers/routers, PCI Express (PCIe) and InfiniBand applications, and base stations. Offering rugged protection, the integrated MOSFET is capable of powering a load from a 9V to 13.2V source with up to 4.0A continuous current.

 The MOSFET is actively closed-loop controlled to ensure that an adjustable current limit is not exceeded when power is applied. The device controls the rate at which voltage is applied, and it unconditionally clamps the output voltage to keep input-overvoltage stresses from harming the load. The DS4560 provides an adjustable power-up timer that causes the device to wait for a predetermined delay time before starting to apply power to the load. Alternatively, the device can be driven with a digital logic signal to implement an externally controlled power-enable function. The DS4560 integrates a temperature sensor with hysteresis. If operating conditions cause the device to exceed an internal thermal limit, one of two actions is taken depending on the version: the DS4560-LO unconditionally shuts down and latches off while awaiting a power-on reset; the DS4560-AR waits until the device has cooled by the hysteresis amount and then restarts.

 Available in a lead-free, 8-pin SO package, the DS4560-LO (latch-off) and DS4560-AR (auto-retry) are each priced at $0.95 (10,000-up, FOB USA).