I'm using this circuit to feed 24V to a servo motor, when I power it on, the TXS stops working and all outputs send 4.1V and even the 3.3V line become a 4.1V.
Is there something wrong with the circuit?
Maybe too much current drown from gate pin?
The motor current is 4.2V at peak

 

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I'm using this circuit to feed 24V to a servo motor, when I power it on, the TXS stops working and all outputs send 4.1V and even the 3.3V line become a 4.1V.
Is there something wrong with the circuit?
Maybe too much current drown from gate pin?
The motor current is 4.2V at peak

There should be NO current into or out of the gate current.
IRF140 is OLD. Does it still work? Have you got the right connections to the TO3 case?

 

There should be NO current into or out of the gate current.
IRF140 is OLD. Does it still work? Have you got the right connections to the TO3 case?

It works, but it shorts the TXS out, idk why. I'm using the IRF1404 because I have them arround from another project, but it coud be any N-Channel MOSFET

 

It works, but it shorts the TXS out, idk why. I'm using the IRF1404 because I have them arround from another project, but it coud be any N-Channel MOSFET

Misread that - thought it was the old IRF140.
If you take the MOSFET out and test for continuity between the terminals, is there any continuity between gate and either of the other two terminals? If so, it's dead.

 

Have you got OE pulled High at power up? I realise the datasheet only talks about it being in the enabled state when high, but I wonder if it could go into a latch-up state in this case also? Best to try it the recommended way, initially pulled down, then enabled once power is stable.

 

Have you got OE pulled High at power up? I realise the datasheet only talks about it being in the enabled state when high, but I wonder if it could go into a latch-up state in this case also? Best to try it the recommended way, initially pulled down, then enabled once power is stable.

It is working normally when connected without the MOSFET, if I power the motor directly it works perfectly, but I need a way to power down the motor if the ALM gets triggered and there's some issue. But without the feature everything is ok

 

Can you drive the motor from a separate circuit, directly from the 3.3V control signal, and bypass the TSX0104 altogether. I'm thinking of something like the circuit below, with the following modifications:

Remove the zener diode VZ, split RC into two equal resistors of about 3k3, and connect the MOSFET's gate to the common point. Rg is a 10 to 22 Ohm resistor to eliminate any tendency for the MOSFET to oscillate. RB could be 3k3. The Logic +Ve supply is your 3.3V rail. You need a reverse biased diode across the motor leads.

 

My guess is that the lack of flyback diode across the motor is the problem, and on switchoff the FET was destroyed by the back emf.