# All Questions

114,519 questions
60 views

### Is this 0.4mm pitch BGA fanout OK?

I have not used any BGA packages before, but (lucky for me) my first one is a 0.5mm pitch device. Since the pitch is so fine, there is no room for vias between the pads, even at the smallest drill ...
65 views

### High pass filter for electret mic to mobile phone

I’m currently working on making a lavalier microphone for use with my phone and gopro camera. I know these types of microphones are readily available and can be purchased fairly cheap, but where would ...
39 views

### Can I extrapolate battery power by a brief observation?

Part of the research we are conducting requires us to estimate how detrimental our proposed algorithm to the battery life of the wearables. To do so, I opted to simply charge the wearable to 100% and ...
49 views

### Nautical map model navigation lights

I would like to create navigation light sequences on old admiralty map of my local area. There are lighthouses and channel markers in area with mix of flashing and times. The single flashes I can use ...
54 views

### Automatic bird feeder with battery using servo

I am considering to create an simple automatic bird feeder with a servo motor and a plastic bottle, like this project, but without remote controller. The thing is that I would like to power it not ...
47 views

### Power supply for led strip [on hold]

How can i calculate the voltage that the led strip want to work and how can i design circuit to supply this led strip with suitable voltage . Thanks all
17 views

### Lion Battery Shutdown Mode and Wake on Charge

I'm currently designing a BMS that doesn't rely on a TI bq-series IC for gas gauging, protections, etc. So far, I have analog circuitry handling over and under-voltage cutoff, overcurrent cutoff, ...
43 views

### quartz and thermostat DIY reflow oven

Due to an error I have ended up with a quartz-infrared oven. 1kW and 9l, for turning it into a reflow oven. I have meant to get one with convection heating but this is what I have received... Not only ...
37 views

### Snubber for Relay Contact Switching Resistive Load

I am working on a redesign of some circuit boards and am looking for a way to save space and potentially switch to surface mount parts. Some of the largest through hole parts in use are for an RC ...
14 views

### Use different adapter for LG 25UM65-p [on hold]

My LG monitor (25UM65-P) has original adapter (19V, 1.7Amp), can I use a different adapter (14V, 2.14Amp) for it? Has this any side effects or negative points?
81 views

### Frequency dependent resistor in real inductor (air coil)?

I tried to measure the resonance frequency of some multi layer air coils. Typical parameters are 0.6 mm copper wire, 3 to 8 layers, and diameter and height are approx 50 mm. I solder a 1 Ohm resistor ...
43 views

### Battery Power Source for Wireless Router & Modem?

I only have access to electrical power via a generator for now, and need to continue to power the wireless router & cable modem even when the generator is out for a good part of the day or night. ...
40 views

### PIC MCU and LCD display 16x2 - strange behavior

I have a LCD display 16x2 connected to a PIC32MX470F512L. On PIC32 I configure all the 6 pins used to interface with the LCD as open drain outputs on 5V tolerant pins, I have 4.7K pull-up on each line ...
65 views

### Amplify an Electret Microphone using an input Jack 3.5mm

First time on the platform, I will try to be as clear as possible, and electronics is a hobby for me, so I'm open to any welcommed criticism. I'm trying to build a little project, recording the sound ...
41 views

### How much power can transit through a power line linking generation and load?

First things first I am not an electrical engineer at all so please bear that in mind when you reply/comment. I am looking at the following problem, I have a power line which connects a windfarm to a ...
38 views

### design a modular system, choosing bus and backplane

Our team has developed a several controller boards for our current Projects for over three years. With little modifications we have used this board in several projects so far. Its structure is as ...
49 views

### Where exactly appears the channel capacitance and Ron when switch on DG442 switches

I have this switch in a circuit, actually there is 30 switches. https://www.vishay.com/docs/70053/dg441.pdf When system is not executing any operation, switches are off. Sx and Dx are not connected. ...
10 views

### Set STEVAL-IDB006V1 in advertising mode

I have a BlueNRG USB Dongle (IDB006V1) Eval board that I'd like to set in advertising mode but I just can't get it there as it throws a HCI_HARDWARE_ERROR_EVENT. I'...
59 views

### Advice on choosing components for a flyback arrangement, for switching inductive loads fast

I have a bank of x6 MOSFETs (SUG90090E) connected in parallel, which I am using to switch a current of maximum 30A through a coil (resistance 1R and inductance 1mH), and am looking for some general ...
35 views

### Is a flex sensor compatible with an 8051 microcontroller? Do we have to use an ADC0808 to connect it to the microcontroller? [on hold]

We are using flex sensors for our project. How can we interface it with an 8051 microcontroller?
49 views

### What is meant by 'Memristance'?

What exactly do authors mean when they say 'memristance' increases by changing certain parameters of an input waveform to a Memristor. Case in point in Strukov's paper it is mentioned that Memristance ...
17 views

### Responsible Battery Reserve Capacity and Low voltage?

It's been asked here, but looking for clarity. How bad is it to undervoltage a 12-volt lead-acid battery? SLI automotive starter batteries list RC (reserve capacity), but I think this a usable ...
116 views

### What will happen if I use laptop charger (3.42A, 19.2V) to charge 12V battery?

The battery's voltage normally is 13.8V when it fully charged. Say I have 5.7Ah motor bike's battery. The laptop's charger will be connected to a battery. The positive port of the charger to positive ...
32 views

### Connecting transformer with single input and secondary two outputs

So I bought a transformer VC16/1/18 and it has two outputs. I want to get the full output on a single output. Does this look correct? The updated one Corrected not Final
46 views

### 78L05 as LM2931 replacement for powering 4XXX logic?

I'm building a project I got as PCB+panel, sourcing my own parts. It takes a clock buffered through CD40106 and runs a CD4017. The sequential outputs of the CD4017 create a programmable sequence of ...
2k views

### Why do BLDC motor (1 kW) controllers have so many MOSFETs?

I have a 1 kW three-phase BLDC motor from China, and I was developing the controller myself. At 48 Vdc, the maximum current should be about 25 Amps and a peak current of 50 Amps for short durations. ...
44 views

### ±12V protection for MIDI input

TLDR; how to make a MIDI input withstand shorting to $\pm12V$? This is a counterpart to this question, I'm asking this as I was inspired by the great answer I got there. I'm designing a MIDI input ...
25 views

### 10A 5v Relay control Submersible (Water motor)

Is it possible to control Submersible (Water motor) with 5v 10A relay. Here is the details of the Submersible water motor. My mains voltage is 225V to 250V If this won't work then what relay should ...
46 views

### Read voltage of the battery that feeds ATmega328p

I am designing a system focused on the uC ATmega328p and I am feeding it directly with a 3.7V LiPo battery. I also have a 3.3V LDO feeding several sensors in the system. My question is the next, If I ...
96 views

### Differential Equation of RC Low Pass Filter

I'm trying to analyse the following circuit to find the differential equation describing the relationship between $V_{in}(t)$ and $V(t)$: Where $C_1 = 2uF$, $C_2= 1uF$ and $R_1=R_2=1k\Omega$...
25 views

### Arc Flash carbonized particles initiation

In panels or switchgears where a tool dropped can initiate a major arc flash. I'd like to understand the behavior if carbonized particles (say from previous short) get into the conductors causing a ...
34 views

### Problem with Bluetooth read range for arduino project

I have been working on an Arduino project for a door entry system in my business office but have encountered a problem. I have a group of 8 working in my office but we have a room which only 3 ...
97 views

### Strongest electrical wire at AWG 24

Is there any ultra strong electrical wire at about AWG24 (0.22mm)? I want something that would be strong as a steel wire rope but also with low resistance that can used as electrical wire.
26 views

### Three phase delta transformer [on hold]

In a three phase delta transformer if one phase burns up then what will be the output of the transformer?
14 views

### Unable to Read GPIO on Atmel SAM4L

I can't believe that this isn't working for me. It should be straightforward, but I've spent the afternoon on it & can't see where I'm going wrong. Hopefully someone will see my obvious mistake. ...
16 views

### Missing values problem in CS mosfet amplifier pspice simulation

I have draw a circuit of mosfet common source amplifier in pspice 17.2 version, but i am facing missing values problem, what have i done wrong??? the problem is; ERROR(ORPSIM-16492): Missing value +...
63 views

### Is there a way to terminate a two conductor cable to a BNC plug?

I have a device with a two conductor cable that I need to interface to a signal conditioner with a BNC input (same as that on a standard oscilloscope). I would rather not use a hacky solution like a ...
42 views

### Decoding circuit with transformer topology

I am studying a circuit used for mobile adaptor, where AC to DC conversion is done through bridge rectifier ABS210. Transformer is used for isolation along with IC LP3783 (Offline PSR Driver) and ...
21 views

### How to link 3 RF transceivers to 1 antenna

I'm not an RF designer, so excuse the newbie question: How would I link three transceivers, say WiFi and two separate bluetooth transceivers, to a single antenna. I have found a 3-way combiner ...
19 views

### Charge Measurement for Piezoelectric Sensor

I want to measure the charge displaced by a force acting on a piezoelectric sensor. The problem is I don't know the sensor so I have no idea how big the current generated by the sensor may be nor what ...
110 views

### How to analyze Microcontroller input-logic-signal without ADC?

I have a signal which is fed to one of the digital inputs of a microcontroller (PIC16F18326). The signal is shown in the image-1 below. This is during the normal operation of the circuit, that means ...
30 views

### Simplest way charge a 3.3V capacitor off of a 9V battery

If we have a series RC circuit in this case, the voltage across the capacitor will exceed 3.3V as the current decreases, no matter what the resistance is, right? This will blow the cap... So what ...
78 views

### Logic Analysis of a 8 bit mcu

I would like to sample the logic on the pins out out of a toy robot's processor and the MCU is an 8 bit processor that operates a max clock speed of 5 Mhz. Does anyone have any recommendations on how ...
22 views

### Shorting the output of both the channels of L298N

Suppose I started with a project requiring the control of motors and ended with using L298N in my project, realizing that my motor only takes around 1.5A when on load. Now, with time I realized that ...
44 views

### Circuit with a single buzzer but multiple L.E.D and switches

I need to design a circuit that has three LEDs, each LED has its own push button switch, but there is only one common buzzer. Goal: when a push button is pressed its corresponding LED should glow ...
56 views

### How could I change a calculator to type letters instead of numbers [on hold]

I thought it would be fun to do I have all the time in the world (not unemployed only 16)
37 views

### battery charging and discharging formula journal link

can anyone give me battery charging and discharging formula journal link? I have been searching for it for a while, but I still can't find the journal that has charging and discharging formula for ...
38 views

There are 2 software tools provided by ST to flash their STM32 MCUs namely STM32CubeProg and STLINK Utility STM32CubeProg Page says: STM32CubeProgrammer (STM32CubeProg) is an all-in-one multi-OS ...