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I made some modifications in the first circuit to make it work with the RESET signal of the ESP01. The RESET signal is connected to the node where the Voltimetes is connected (between the 100 ohms resistor and the diode. The 3,3k resistor must be removed, I put it to simulate the internal impedance of the RESET pin. Hope it works for you


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Use a P-channel MOSFET eg. AO3401A to cut Vcc. Low to the gate = ON. simulate this circuit – Schematic created using CircuitLab Add a 1K resistor series with the TRIG input and make sure that you drive TRIG low before shutting off the Vcc and do not drive it high until after Vcc has been turned on. Also do not drive ECHO high as an output (it should ...


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How about some numbers? 0.775 volts into 600 ohms is one milliwatt. A blue LED needs 3 volts and 20 milliamperes. That's 60 milliwatts. If you collect energy at 1 milliwatt for 60 seconds then you will have enough energy to light that blue LED for one second. Typical microphone output levels are about 1/1000 of one milliwatt. It would take about 60000 ...


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The 1.8 Vdd input on the chip only powers the ADC's and some digital logic. Unless there is internal damage, the pin should not draw anything like 95 mA. Possibility #1: in this land grid package with 0.8 mm pitch between pads, the 1.8 Vdd pin (11) and the GND pin (12) are adjacent. Are you sure you don't have a solder bridge between those pins under the IC? ...


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An Iridium 9603 module is the smallest satellite comms device that I know of. It’s about the same size as a patch antenna (which you’ll unavoidably need).


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Have you considered another microcontroller? The AVR is not exactly the most low power on the market. There are XLP PICs and MSP430 too (the MSP430 is 16 bit, too). Also you should check the power budget of your sensor; make sure you actually turn off everything you don't need while not sleeping (the ultrasound analog circuitry sucks quite a lot of milliamps ...


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You could use the watchdog timer to sleep for 15 minutes by going into deep sleep mode right after waking up as many times as needed to reach 15 minutes. You can keep track of how many 8 seconds cycles you have slept with a variable. Contents of the chip's sram are preserved during sleep.


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Have a look at the LM5164 100V in, 5uA at 40V Iq? Depending on the controller, you can either linear from 12V to 5V (low power) or use a small switcher (higher power). Note: most buck converters efficiency drops off when you start talking sub milliamp currents and 12V micro-watt BUCK is still not that common. Simon


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Idle, sleep or stop is a different names for similar processes in different MCU. Usually microcontrollers have a few oscillators, and one of them is main. Programm runs from main oscillators, some periferals,like ADC, UART, timers, etc run with another oscillators,mostly slower then main. Then process end, they wake up MCU from that mode. It is all for ...


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Yes, "reading data from a sensor is an instruction which the CPU needs to execute". But the sensor can do other work while the CPU is stopped. For example, the ADC peripheral can do the conversion (i.e. sampling the analog signal and converting it to bits). The ADC peripheral is powered with a different clock than the CPU. The ADC clock is not ...


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This could be due to many reasons and by inspecting the cause of each possibility you may troubleshoot the problem depending on your context: Brownouts: high electricity demand even temporarily like a start-up of heavy equipments. related in some cases to the weather condition. Try to correlate the timing. construction project or civil works in the ...


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