Hi,
I've been assembling an opto-isolator sensor, and after noticing that the output voltage during the transition point is not digitally ON-OFF, I decided to add a comparator. After browsing, I've found a schematic using the LM741 in a single supply mode used as a comparator.
I hope to get a good result. However, the transition is not as I expected. I do have an ON-OFF state but the voltage swing is too thin. The high state is 4.2 V and low state is 2 V, which is totally USELESS to drive my ATMega8535. It still see it as a high state on both condition. I use 5V for the Vcc.
I tried to browse again and found out that LM741 is not recommended for comparator. Is there any mistake on my design? or should I just change the LM741.
The thing is that I already assemble them on the PCB. Is there any comparator IC which has similar pin configuration? at least the Vcc, Gnd, V+, V-, and Vout.
I admit it's an unnecessary mistake since I only look at the LED and do not measure the output voltage, when I tested it on my bread board. Damn.
Here's the schematic:
**broken link removed**
I've been assembling an opto-isolator sensor, and after noticing that the output voltage during the transition point is not digitally ON-OFF, I decided to add a comparator. After browsing, I've found a schematic using the LM741 in a single supply mode used as a comparator.
I hope to get a good result. However, the transition is not as I expected. I do have an ON-OFF state but the voltage swing is too thin. The high state is 4.2 V and low state is 2 V, which is totally USELESS to drive my ATMega8535. It still see it as a high state on both condition. I use 5V for the Vcc.
I tried to browse again and found out that LM741 is not recommended for comparator. Is there any mistake on my design? or should I just change the LM741.
The thing is that I already assemble them on the PCB. Is there any comparator IC which has similar pin configuration? at least the Vcc, Gnd, V+, V-, and Vout.
I admit it's an unnecessary mistake since I only look at the LED and do not measure the output voltage, when I tested it on my bread board. Damn.
Here's the schematic:
**broken link removed**