Design a logic circuit
Budget: $30 – $250 USD
I need a circuit design. In my application, a 9v battery supplies power to an Arduino Uno. The 5v output available on the Arduino is used to power a GPS module ('GPS Module Receiver, Navigation Satellite Positioning NEO-6M' available on Amazon; image attached). The GPS module has a Pulse Per Second (PPS, one cycle per second) pin that is active only when the module has obtained a fix on a satellite set and begins tracking. Before tracking begins or when tracking fails, the PPS pin is at zero volts.
When the PPS pin is active, it produces a square wave pulse train, 1 Hz, 3.3v amplitude and 100ms duration of each pulse.
The supply voltage powering the GPS module is 5vDC and it is continually on, regardless of whether tracking has or has not been obtained. In other words, the GPS module is powered continually even if the PPS pin is active intermittently. 5vDC from the Arduino output will be the only source of power in this circuit.
Design a circuit to do the following –
1) When the PPS pin is active, set a timer output or logic output to 5vDC (slightly less than 5vDC due to efficiency loss). The output should be DC steadily on. If an LED is connected to this output, it is steadily and continually lit in this condition.
2) When the pulse train is not available; that is, there is no square wave voltage cycle, set the timer or logic output to zero volts. If an LED is connected to this output, it is completely off in this condition. Reminder: the 5vDC supply voltage to the GPS module remains on even when the PPS pin is inactive.
3) Breadboard test the circuit. I would prefer that you also test this circuit with output from an actual GPS module and its PPS pin; that is, not relying only on a function generator to substitute for the PPS output.
Design an effective and efficient circuit; use a minimum of components that have very small power requirements; deliver the design to me.
When the PPS pin is active, it produces a square wave pulse train, 1 Hz, 3.3v amplitude and 100ms duration of each pulse.
The supply voltage powering the GPS module is 5vDC and it is continually on, regardless of whether tracking has or has not been obtained. In other words, the GPS module is powered continually even if the PPS pin is active intermittently. 5vDC from the Arduino output will be the only source of power in this circuit.
Design a circuit to do the following –
1) When the PPS pin is active, set a timer output or logic output to 5vDC (slightly less than 5vDC due to efficiency loss). The output should be DC steadily on. If an LED is connected to this output, it is steadily and continually lit in this condition.
2) When the pulse train is not available; that is, there is no square wave voltage cycle, set the timer or logic output to zero volts. If an LED is connected to this output, it is completely off in this condition. Reminder: the 5vDC supply voltage to the GPS module remains on even when the PPS pin is inactive.
3) Breadboard test the circuit. I would prefer that you also test this circuit with output from an actual GPS module and its PPS pin; that is, not relying only on a function generator to substitute for the PPS output.
Design an effective and efficient circuit; use a minimum of components that have very small power requirements; deliver the design to me.