Hi,
I firstly would like to add I'm doing an ultrasonic project. For the receiver I've simulated a circuit which amplifies 100mV input to around 5V using an Opamp.
However when I check using an oscilloscope at the output of the Opamp the amplitude is basically 5V DC (ie. a straight line), I'm expecting an amplified sine wave instead.
I've fed at the input to the circuit a signal that is meant to simulate what the receiver ultrasonic device picks up (the transmitter transmits a square wave but the receiver receives a weakend sine wave echo). A sine wave with 100Vp-p amplitude with a frequency at 40KHz (ultrasonic) is inputted.
Any ideas?
Thanks everyone!
BTW I've included the pics of the simulation using multisim. The yellow line from channel A is the final opamp output and the cyan sine wave from channel b is the input signal.
It's my wish once this is done to put the amplified sine wave at 5Vp-p through a comparator (with reference at 5V, same as before but comparing against 2.5V provided by two 1k resistors) to produce a clean square wave that the microcontroller can make sense of.
PS: I've done it all on multisim as I don't have access to a real oscilloscope till next week as well as I don't have the components on hand will need to order them once I know that this works for certain. I've had troubles with my previous receivers so I'm hoping this design will work out.
PS2: yes it was a 2 stage amplifier before but I removed the 2nd amplifier as it wasn't necessary. Also a filter isn't necessary as well I believe so.
I firstly would like to add I'm doing an ultrasonic project. For the receiver I've simulated a circuit which amplifies 100mV input to around 5V using an Opamp.
However when I check using an oscilloscope at the output of the Opamp the amplitude is basically 5V DC (ie. a straight line), I'm expecting an amplified sine wave instead.
I've fed at the input to the circuit a signal that is meant to simulate what the receiver ultrasonic device picks up (the transmitter transmits a square wave but the receiver receives a weakend sine wave echo). A sine wave with 100Vp-p amplitude with a frequency at 40KHz (ultrasonic) is inputted.
Any ideas?
Thanks everyone!
BTW I've included the pics of the simulation using multisim. The yellow line from channel A is the final opamp output and the cyan sine wave from channel b is the input signal.
It's my wish once this is done to put the amplified sine wave at 5Vp-p through a comparator (with reference at 5V, same as before but comparing against 2.5V provided by two 1k resistors) to produce a clean square wave that the microcontroller can make sense of.
PS: I've done it all on multisim as I don't have access to a real oscilloscope till next week as well as I don't have the components on hand will need to order them once I know that this works for certain. I've had troubles with my previous receivers so I'm hoping this design will work out.
PS2: yes it was a 2 stage amplifier before but I removed the 2nd amplifier as it wasn't necessary. Also a filter isn't necessary as well I believe so.
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