Fuse for 10 A, 36 V with automatic reset?

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pitchshifter

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I'm working on a motor driver PCB and need some sort of fuse. It should break the circuit at 10 A, and handle voltages up to at least 36 V.

The thing is that I need an automatic reset/retry, either within a few seconds or when power is cycled. Without physical access to the PCB.

What options are there?
PTCs Don't seem to go that high in current/voltage? Maybe a current sensing circuit and a power mosfet?
 

Hi,

there are 10A resettable PTC fuses with 30V rating.
Maybe good for a test or a hobby project, but not good for reliable high volume production.

****
Why no motor current measurement and control the driver?


Klaus
 

I'm afraid I need 36 V.

The drivers have separate current limiters, but I need an additional layer of safety if the drivers or other high current output fails.
 

The retry stage can consist of a 555 IC, configured to send low duty cycle pulses.

The simulation shows it entering this state when the input (lefthand) goes high. This signal can come from a current monitor at your load.



There is a hurdle because you'll need some logic circuit that permits the input to go low again only during a retry event, and only if current is less than 10A. A solution could be a memory circuit such as an RS flip flop.
 

PTCs are great in theory but in reality they're far from ideal with high resistance, significant temperature derating and large size/cost that increases with both current and voltage.

There are a large number of load switches/mosfet controllers/hot swap controllers/current sense amplifiers and other ICs that provide solid state current limiting options and fusing functionality.

For example:
INA202, current sense shunt + mosfet

Or if you can be less precise with the shutoff current there are many ICs like this for the automotive market:
**broken link removed**
 

Thanks everyone, the INA202 was just what I needed!
 

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