Questions tagged [low-power]
Low-power refers to electronics that are designed to use less power than their common counterparts. This is often a requirement because of limited available power, as in battery operated devices, or in cases with limited cooling capabilities, as in notebooks.
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Any way to have MSP430 wake from sleep and immediately start executing the next instruction after the sleep, avoiding calling into the ISR?
I am executing a simple state machine that steps based on a pin change and sleeps between steps. A significant amount of time is spent in the overhead overhead of calling the ISR on each pin change, ...
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FreeRTOS is slow to wake after long processor sleep
(Cross-posted on Stack Overflow)
I'm using FreeRTOS in an application which requires the processor to sleep in low power mode for a long time (as long as 12 hours), then wake up in response to an ...
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Isolating low-current, low-voltage digital signals
I'm working with a battery-powered sensor that allows reading its measurements using two digital signals - a clock and a data line. The clock speed is abount 3kHz. In addition to those two signals, ...
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STM32L4 LPTIM as pulse counter of intermittent pulses fails when initializing with no pulse
I'm working with LPTIM as a Pulse Counter on a STM32L432KC, I have a rain gauge connected to LPTIM1 (PB5) and a anemometer to LPTIM2 (PB1). Both configured on STM32CubeMX as Standalone: counts ...
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Ultra low power battery
I am currently in the middle of a project and I am quite unsure of what type of battery and battery charger I should be using. To be honest I have never worked with battery or battery charger yet.
In ...
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Problem with battery power circuit
I am a 14 years old boy and I am currently making a MacroPad with a 3.7V battery and a charging circuit but powering the circuit with a battery does not seem to work. I also have made some ...
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Is energy lost on a powered, long, but unused DC power line? And how?
I am designing a super low power sensor system with a master and multiple, simple clients connected with a 4 wire bus (differential signals, GND, DC low voltage VCC on shielded twisted pairs).
The ...
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209
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MCU self power off switch
I want to create a auto power off circuit for a battery powered sensor to preserve the battery. The switch will be a reed type and the trigger pulse will be brief (~70 ms is my guess, shorter than ...
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Bodyheat powered microcontroller
Old Post and even older Post I came across before posting this question. The answers by McMahon and Alexeev are pretty much what I was thinking:
human energy source: ~100 W
skin surface: ~1.75 m2
⇒ ~...
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ESP8266 using DS3231 to wake up from deep sleep
I am using the Arduino IDE to program the ESP8266 and am able to set the time, alarms on the DS3231 and test to see that they are firing.
My problem is that I would like to use the SQW output to wake ...
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Shortcircuit protection using transistors
I'm designing a short-circuit protection circuit for x2 AA battery (3V) and I'd like some tips from the community on how can I make it a low power mode circuit.
When V_out is short cirtcuited, the ...
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Discharge protection circuit for 2S Li-ion
I'm looking for a overdischarge protection circuit for two 18650 in series. Preferably not a module. Discharge current is max 1mA. Charging is done in a separate charger
My situation is a circuit ...
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Powering down parts of a pcb to conserve power, is it possible? Any caveats?
I'm building a USB 2.0 bus-powered STM32F429-based audio device that is able to run in a stand-alone mode from a phone charger, or running as a USB device when connected to a computer.
To comply with ...
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Low power circuit design
I want to design a low power circuit with stm32l micro and LoRa Module as its radio to send a sensor data to a gateway. The circuit is powered with a non rechargeable battery.
My problem is about its ...
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USART on STM32F411 reads junk after MCU wakes up from STOP mode
I am working on a board that uses an STM32F411 connected to a bluetooth module over USART. One of the goals is to enable Low-power consumption in STOP mode.
A brief summary of the platform:
The ...
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Lowest energy wireless protocol for specific wireless sensor node
There are so many options for low-power wireless communication these days. BLE is everywhere, and many other manufacturers try to push their protocols as well. LoRa, Dust, Zigbee, Thread, Sigfox, etc.,...
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Low Current Consuption on a Voltage Inverter
I'm working with a uC and a Bluetooth Module. I need the lowest current consumption in this project because it is intended to be a mobile device. Thus, I'm using sleep modes on the uC. Now, I've ...
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466
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RF limiter for -20dbm
I am working on a receiver in which I would like to limit the RF power at input to -10dBm to -20dBm, the receiver is working for frequency 1GHz. I Have checked pin diode limiters and shottkey diode ...
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398
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Bipolar energy harvesting circuit
I'm planning an energy harvesting circuit using LTC3105 (400mA Step-Up DC/DC Converter with Maximum Power Point Control and 250mV Start-Up).
The problem is that my energy source is bipolar, although ...
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Shut down circuit sections
I am currently devising ways to shut off different circuit sections in an embedded circuit. Here is a breakdown of what I am doing and my initial idea. Currently I have a micro controller which is ...
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Reducing current consumption for a PIC16 / Sleep mode
I would like to operate a PIC16F628A in sleep mode with less than 1 µA. For that I have switched off all ADC, peripherals, etc.. But about 7.5 µA is the lowest current I can achieve.
I have found a ...
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esp8266 (ESP-07S) draws 100 micro amps in deep sleep instead of 20 as documented
I have a quite simple circuit using ESP-07S module (esp8266 chip, no USB, no LEDs).
The device, after performing some operations enters deep sleep and waits for a button connected to RST to wake up (...
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STM32WL ADC during STOP modes impossible?
I want to sample a signal with the ADC for a certain time (one-shot) and keep the CPU in the lowest power mode possible.
ADC is triggered by TIM1 and DMA is set up.
When using SLEEP mode, ...
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332
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ESP32 power efficient battery monitoring
I'm trying to implement a simple battery monitoring circuit for an ESP32 that gets completely shut down and then powered on periodically. I don't want to drain the battery and/or backpower the ESP32 ...
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2
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How to put MCP3008 into sleep mode
I am using an MCP3008 ADC connected to a Seeed Studio Xiao nRF52840.
I am using the adafruit library #include <Adafruit_MCP3008.h>
It operates as expected, ...
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170
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P-channel MOSFET + op-amp ideal diode
I'm replicating the ideal diode circuit from Crutschow.
I'm using the op-amp flavor in order to get a very low quiescent current.
The P-channel MOSFET will be a NTMFS002P03P8ZT1G.
My questions are :
...
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50
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Understanding average Iq of buck boost converter (skipping and switching modes)
I'm trying to pick a buck boost converter for a low power, small battery, long life device.
The datasheets specify different supply currents for different modes and I just can't wrap my head around ...
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66
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Multiple voltage diode protection
I'm attempting to build a circuit that can be powered from either a external power connection (+12V in the diagram), or via USB (VBUS). I realized that I also want to be able to connect the USB for ...
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394
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Ultra-low power low battery disconnect circuit
I am trying to design a circuit to replicate the behavior of the LTC4071 battery charger/protector IC (see datasheet here). In particular I want to replicate the low battery disconnect function which ...
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USB Data Line Current Value
I am designing USB2.0 hardware input but i don't have enough space on my PCB area. I searched many site but I cant find any information about D+ D- data lines power consumption. I am using 15R ...
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702
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Power 5V and 3.3V components from li-ion battery
I want to make a portable device that runs of a rechargeable li-ion (4.2-2.7V) batteries. I have components that run on 3.3V (ATmega328P ,GPS) and some LEDs (5V.)
There are multiple ways I can think ...
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55
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Power input management help?
I'm working on a power supply management circuit for a small 30 mW device powered by alkaline batteries for months in remote locations, used by both skilled and unskilled users. The device will have ...
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ESP32-WROVER-E low-power custom board validation
I recently finished my degree in Electronics Engineering. My experience with that degree is that you learn a lot of things, but you don't go really deep into any subject.
So I'm trying to solve that ...
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How can I get different voltage inputs from a high voltage power supply?
I want to use a 5 kV DC supply to power a low-current (0.5-3.5 mA) circuit in a microfluidic device.
I would like to create two input voltages from this power supply to have a 300 V drop from 4.3 kV ...
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STM32L1 Stop mode GPIO setup
in my project where I use stop mode, I would like to configure 4 ways to wakeup.
On four gpio I have an EXTI (two of them only increment the variable), two of them change the state of the variable to ...
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Can I use "ideal diode" in series in solar cells?
i have a small experimental solar panel system to gain knowledge before moving on large power systems.
My system is 5 solar cells in series, each 5.8V 0,52A (peak power). So total is 29V 0,52A (about ...
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Power consumption on LPDDR4 command bus - impedance options
I'm trying to solicit and opinion on the use of the 60 ohm transmitter/transmission line/ODT for the command bus of an LPDDR4 bus would be better than 40 ohm target impedance. The system uses an ...
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Does my PCIe platform support CLKREQ#?
I succeeded entering ASPM L1.1 and L1.2 for my device. After entering ASPM L1.1 or L1.2 and trying to initiate to exit from Host side, I saw some hosts that are:
• Able to initiate an exit from ASPM ...
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STM32L1 GPIO pin configuration - Power supply current increase due to pin with open-drain setup
Setup
I have an STM32L151 mcu(application processor) and on its PB5 pin I have a peripheral (SARA-N3) connected. The requirements for the peripheral are that the pin is configured as an open drain ...
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Feather 32u4 too much current draw
I am trying to build a battery-powered application using the Feather 32u4.
I need a timer to trigger every 120 seconds (although Timer1 with it's 8 second limit would suffice for the beginning), thus ...
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Energy-efficient Power Supply (PSU) circuit for STM32WLE Microcontroller with 1.8-3.6V for 150mA peak current
I am thinking how to best (best=lowest energy consumption and standby current) power a STM32WLE:
https://www.st.com/en/microcontrollers-microprocessors/stm32wlex.html
The power management of the IC ...
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Would an LM7805 need a heatsink stepping down two stacked LiR2032/CR2032 (3.6V X2) batteries?
Okay, I'm terrible at anything electronic, especially when it comes to building from boards (think rudimentary understanding). I've built a few PC's in my day, but piecemeal, not from scratch. Keep ...
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Constant voltage source from battery and main power supply for power LED
I want to power a power LED from a lithium-ion battery and simultaneously from a 5V power supply if the device is plugged into the main voltage. My LED driver demands 3.3 V and up to 800 mA. The ...
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Solar-powered 74HC14 LED flasher: oscillators interfere
I am building a "nocturnal solar engine" with two LEDs flashing independently, following the description at the old Solarbotics website. I am essentially rebuilding the same circuit. The ...
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Piezo cantilever energy harvester: how to mesure such small power?
I am currently designing a piezo energy harvester and I would like to modify the resonating frequency to maximize the energy recovered(for exemple by changing the center of mass of the cantilever). My ...
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Getting most power from low voltage solar powers, each different angle
I have a specific problem. I have 10 small solar panels, each max 5.5V and 100mW power. Each one is at a different angle. I want to get the most power out of it. Cost is not really a problem, but I do ...
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Nano Power Soft Latch
I need to latch an INT output with a time width of 7 ms. This signal is generated by an RTC clock and I need to enable an LDO with it. The LDO powers an MCU, which at the end of its program should be ...
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Supply current of Nanopower OpAmp
I'm using MCP6044 Quad OpAmp (Datasheet) for battery powered PIR sensor, it works fine but draws too much current. When I plug it to 3V source (VDD: 3V, VSS: GND) with no load it draws around 550uA, ...
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Using an NO switch to close to ground as an interrupt
I'm designing a circuit that supplies power via USB to an Arudino. The USB power runs through a 3v3/5v dual regulator. I'd like to use a small tactile switch in front of the IN lead on the regulator ...
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Electrical calculation
I'm need to calculate the how long it will take to charge a battery using a solar cell. I am not taking any charge curves into account, I just want to get a close answer before I run the experiment. I ...
