Hi,
I was unable to purchase the required circuit so I needed to figure out how to build it. I have been experimenting with this circuit for a while and have tried a few different alternatives with varied results. I'm close to the desired result using mosfets and a NAND gate, however I'm hoping to simplify and increase the circuit's reliability using an op-amp. The goal is to run a forward or a reverse camera depending on the direction of the brushed electric motor. The signal is piggybacked off the two power cables from the speed controller. The signal is 0.5V to 3.5V dc when in reverse and -0.5V to -3.5V when in forward. The negative forward signal needs to be cancelled out for the desired output but i'm not sure if R6 energises M1 to switch the signal on when the input voltage is negative or low side. LTSpice is giving strange and varied test results, so I'm not sure if I've got the circuit right or am operating LTSpice right. My questions are, will this circuit give the desired outputs? and is there a more readily available op-amp that will perform the desired function with the same connection, than the AD8691? as I can't get that one in Australia. Thank you in advance
I was unable to purchase the required circuit so I needed to figure out how to build it. I have been experimenting with this circuit for a while and have tried a few different alternatives with varied results. I'm close to the desired result using mosfets and a NAND gate, however I'm hoping to simplify and increase the circuit's reliability using an op-amp. The goal is to run a forward or a reverse camera depending on the direction of the brushed electric motor. The signal is piggybacked off the two power cables from the speed controller. The signal is 0.5V to 3.5V dc when in reverse and -0.5V to -3.5V when in forward. The negative forward signal needs to be cancelled out for the desired output but i'm not sure if R6 energises M1 to switch the signal on when the input voltage is negative or low side. LTSpice is giving strange and varied test results, so I'm not sure if I've got the circuit right or am operating LTSpice right. My questions are, will this circuit give the desired outputs? and is there a more readily available op-amp that will perform the desired function with the same connection, than the AD8691? as I can't get that one in Australia. Thank you in advance