Slope detection circuit or Edge detection circuit proposal

[zero0d]

Hi All,

i need some help to put me in to right detection and to choose the right circuit for slope or rising edge detection circuit using OPAMP or Comparator or something else

Here is my block diagram in attachment:

1) i have a hall current sensor eg from Infineon PN: TLI4971-A025T5-E0001.
I'm applying current pulses to the hall sensor:
-> The current can be from 100mA to 10A ( the hall sensor will produce voltage with 1us delay at the output from 0V to 5V depending on the current)
-> The current pulses can have ton_min= 10us , ton_typ = 100us, and a typical frequency of 100Hz to 1kHz

2) on the other hand i have a mcu of FPGA digital input, when goes from low to high ( means current is pressent), when goes from high to low ( current not present, but this transition is not critical)
Primarily i want to detect the current is present.

3) So I'm looking for a circuit that can detect the rising slope and give a high(3.3V or 5V) to the MCU for the given range of currents (100mA to 10A)

I was thing about a non-inverting differentiator or a input AC coupled non inverting OPAMP with high gain and high speed GBW, but i can't find much data on those approaches.

Thank you and Br.

[Terry Bites]

Something like this? Adjust R2 for threshold.

[zero0d]

Hi Terry,

i tried the simulation in TINA-TI, but i didn't get a behavior that i want. (Attached, need to run Analysis Transient)

One thing i noticed in your picture is that you didn't use square signal on the input, why? the signal from Hall sensor is square ( in my sim i used 480mV amplitude that represents 10A current)

[zero0d]

Ok, i now got it to work , need to change the threshold very  low -> I set the R1( your R2) to 1k.

Also i have to check if it will work with 5mV input.

It now works, but it is inverted.