Criteria:
- Supply: 9V Battery with LP2950 5V regulator
- wake up a PIC 10F206 (using weak Pull up) with a low power (< 200 uA) 38KHz IR 940nM IR detector
Using an op-amp or comparator to do this appears to require too much standby current > 1 mA
Using LTSPICE models based on a minimum 45nA source current measured with several different IR detectors ... both NPN and IR Diode Detectors were measured ... the source current is dependent on distance from the IR Source ... measured at approximately 3' to 4' from the source. ... current was calculated based on a 5V Source and 20M series resistor ... Voltage measured with x10 scope probe and ac coupled 50mV/Div
Circuit 1
Circuit 2
In both circuits the LTSPICE models show the saturated switching occurs around roughly 45nA (the IR detector is simulated with a Current Source)
Circuit 1 doesn't appear to work in real life ... perhaps the 2N7000 LTSPICE model needs tweaking
Circuit 2 is so sensitive it is affected by sunshine ... when the sun is blocked the circuit does appear to work the way the LTSPICE model predicts
Any suggestions would be appreciated
- Supply: 9V Battery with LP2950 5V regulator
- wake up a PIC 10F206 (using weak Pull up) with a low power (< 200 uA) 38KHz IR 940nM IR detector
Using an op-amp or comparator to do this appears to require too much standby current > 1 mA
Using LTSPICE models based on a minimum 45nA source current measured with several different IR detectors ... both NPN and IR Diode Detectors were measured ... the source current is dependent on distance from the IR Source ... measured at approximately 3' to 4' from the source. ... current was calculated based on a 5V Source and 20M series resistor ... Voltage measured with x10 scope probe and ac coupled 50mV/Div
Circuit 1
Circuit 2
In both circuits the LTSPICE models show the saturated switching occurs around roughly 45nA (the IR detector is simulated with a Current Source)
Circuit 1 doesn't appear to work in real life ... perhaps the 2N7000 LTSPICE model needs tweaking
Circuit 2 is so sensitive it is affected by sunshine ... when the sun is blocked the circuit does appear to work the way the LTSPICE model predicts
Any suggestions would be appreciated