Need to design an IR Receive amplification circuit for digital processing

[budm]

Re: Need to design an IR Receive amplification circuit for digital processing

What I basically want to do, is when the line that I labeled as 'IR Signal' goes below 4 volts, I want that transistor to turn on HARD so that it sinks that D2 pin straight to ground. Normally (at idle), the 'IR Signal' line is at 5 volts.

(see attachment)

What is the spec of the U1 IR receiver?
So you want IC A1 input to be active low then, so PNP transistor will be used so when IR receiver U1 output goes low it will turn on the PNP transistor (Collector is ground, Emitter to A1 input)

[stj]

Re: Need to design an IR Receive amplification circuit for digital processing

ir recievers are complex devices containing filters and amplifiers etc,
you cant boost the output.
you can replace it - some are more sensitive than others.

also, look at the transmitter - specially the capacitor, the led and the series resistor.
the led is pulsed at high current,
the capacitor holds the current to stop the battery from being overloaded.

[EasyGoing1]

Re: Need to design an IR Receive amplification circuit for digital processing

Show us the schematic of the existing IR receiver, also the remote itself.

What I basically want to do, is when the line that I labeled as 'IR Signal' goes below 4 volts, I want that transistor to turn on HARD so that it sinks that D2 pin straight to ground. Normally (at idle), the 'IR Signal' line is at 5 volts.

(see attachment)

[EasyGoing1]

Re: Need to design an IR Receive amplification circuit for digital processing

Show us the schematic of the existing IR receiver, also the remote itself.

Attached is the circuit, I don't have a schematic for the remote controller, but it's just a standard remote controller that puts out infra red light signals in a square wave pulse that the Arduino can analyze and use according to the code created and uploaded into the arduino.

[budm]

Re: Need to design an IR Receive amplification circuit for digital processing

Show us the schematic of the existing IR receiver, also the remote itself.

[EasyGoing1]

Hello,

What I am trying to do, is add to a project that I have already created and am using successfully.

What I have noticed, is that when batteries in my IR remote control get marginally low, the project I'm using doesn't get accurate information from the remote, so I need to replace batteries in the remote - in my opinion - too frequently.

The input pin in the Arduino triggers interrupts when it crosses a threshold between 2.2 and 2.4 volts. If voltage fluctuates between 2.2 and 2.4, then the interrupt constantly triggers.

I've noticed that when the IR receiver is idle, it feeds roughly 5 volts to the input pin and when I trigger it with an infrared signal, it goes down to around 1.1 volts at its lowest value.

The IR Input pin is configured to idle in an INPUT_PULLUP mode, which means if nothing is connected to it, it will always be right around 5 volts, so I only need to pull it to ground when that IR sensor gets below 4 volts or so.

SO ... what I'm thinking, since most standard transistors will turn on at a base value of around 1-ish volts, I need a circuit that will stay off when the voltage is at 5, but then turn on HARD when the voltage gets below 4 which would let me sink that input pin straight to ground through the collector ... so I basically need the reverse behavior of a "normal" transistor with very little saturation margin as the voltage on the base begins to change and I don't know how to create such a circuit.

Any input or ideas on where or how to direct my pursuit on such a circuit would be much appreciated.

Thank you,