TLV9022: Amplifiers forum

Hello Jenil,

It is a bit difficult to read your schematics - I cannot zoom in close enough to see the details fully and some are obscured.

Can you either please post a zoomed-in view of just the schematic (screenshot using Windows+Shift+S then select the schematic area) Or, even better, can you package your simulation and post the ZIP file? Or both!

I am posting it as a link, does that work? ill zip the files and send it too

/resized-image/__size/640x480/__key/communityserver-discussions-components-files/14/Screenshot-_2800_1473_2900_.png

Jenil, I still cant view your image as it is blurry on my end. could you send the zip file of your project?

Thank you Clemens! 

Jenil, I believe it needs to be connected like this as this since for your circuit, when the fet opens, there is no GND connection for your input source.

thank you for your response, I have changed the design specs a little, Instead of detecting between 0 to 0.1, I have the signal being amplified and filtered first so that it got from 0 to 2.5V, hence if the signal is 2.75, then I want the output to go LOW instead of high compared to last time. I have used the required hysteresis so that my output trips from 5v to 0 but because my input it between  0 to 2.5 my output still has the chance of going back high if the input goes below the lower threshold. I have connected the mosfet to ground like this, but I am still confused how it will workout. Sharing both the files and the image:


ZIpped files.zip

(also I am using single supple)

Hello Jenil,

Thanks for the update. Are you still trying to latch the output? I am not sure what you're trying to do. It seems like this circuit might be better suited with TLV9032 the push pull version to drive that fet. 

Hi chi,

so instead of trying to drive the out put using the FET, I’m using it to change the reference voltage…. My goal is latch it to 0 when there’s a problem and eventually I’ll use like a reset signal to disable the mosfet and set it back to 2.75 volts reference. I

i was using an open drain because I have been using it at other places (I have a window comparator else where) so I thought that I could just that to avoid buying another chip entirely..however I’m open to any advice

Jenil,

Not sure if this is what you're looking for but here the output latches high but I use an NMOS instead. I am using TLV9032 the push pull just to reduce  pull up resistor 

Yes, is it possible to reset this? I have been stuck at trying to reset after it passes the threshold using a reset signal..that was my main problem

Also I changed my design for it to go from 5 to 0 instead of 0 to 5 when there’s overcurrent 

yeah, I understand that but because I will eventually be using space rated components, I have been asked to design it this way with equivalents available

Hi, I can see the reset working but I wanted the latching behavior as well. Would be great if you could show the latching + the reset behavior.

I was thinking of the following approach:

1. pass my signal from 0-3V through an opamp -> raise the ground to 1 V -> all my signals are now between 1Vto 4V
2. set hysteresis (upper threshold: 3.75V, lower threshold: 0.5V)
3. once it latches, i.e. crosses 3.75V, it stays 0.

4. for it to turn back on, the input must go <0.5. Here I was thinking of connecting a mosfet to the input connected to the reset signal and ground so that it turns the signal low (probably with a pull-down resistor)

here's the circuit and the response without the mosfet connected.

/resized-image/__size/960x720/__key/communityserver-discussions-components-files/14/Screenshot-_2800_1477_2900_.png8867.Pictures.zip