Hi. I have a 2 stage op amp design that I have some questions on. The 1st stage output is the output from a photodiode signal. This signal is then fed into a level shifted DC blocking capacitor to block out the background white light from the photodetector. This is is then fed into a second stage op-amp. The output from the 2 opamps are shown in blue (first) and green (second). I was wondering if it is possible, with the configuration I have, to pull the output to ground (it currently goes low to .7V) and tune the duty cycle to 50%. There are 2 more op-amps on this chip (LM324) that I can use. I would rather not add extra components such as flip flops or schmitt triggers for pulse shaping. Is there anyway I can acheive this? Thanks.