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### My sister has a hover round scooter (or whatever their called)

The batteries are bad. While trying to figure out how to replace them I have come across these numbers Mu-1slda 12v27ah C/5 12V32Ah C/20 Does the new batteries have to have the exact numbers or ...
15 views

### How to measure or estimate the phase delay between two analog input channels of this board?

There is a 16-bit data acquisition board with +/-10V range which multiplexes analog inputs and buffers the data to the PC. Specifications are given here (DAS6036 is the model in question). Now I need ...
96 views

### Breakpoint Alters PIO Interrupt Behavior - ATSAMV71

So I'm baffled by this... I'm working with an ARMv7-M microcontroller and GCC compiler, debugging some code where I'm trying to enable an interrupt. I'm trying to do the following: enable an ...
90 views

### Voltage divider on differential op-amp

I need to measure the voltage across the R2 (VA - VB) but it is above the common mode voltage range of op-amp. simulate this circuit – Schematic created using CircuitLab How could I do that? ...
11 views

### Compilation and synthesis work both fine but the wave simulation seems stuck

The following code is an attempt to implement the responses given in this post, a program that takes in its entry a real number coded in 2's complement in a 16 bit std logic vector (the integer part ...
60 views

### Is one big via better than multiple small vias when changing power traces and ground between layers?

I'm confused about the via placement in power traces either to change layers as part of routing the main supply or to get to component pins from a layer different to where the power trace is located, ...
57 views

### Read 8 serial ports at the same time with an Attiny

I'm building a MIDI merger, based on a Attiny (either 84 or 85). How to read multiple serial ports at the same time (for example 8 RX input)? I can't find the blog article anymore, but I think I did ...
23 views

### How is the impedance of a circuit calculated when non linearity is introduced from a switch

What is the impedance of the following circuit if the switch operates at the same frequency with the input voltage. Since the switch introduces non-linearity to the circuit, how can I calculate the ...
335 views

### Do EVs with a DC motor require an inverter and/or/nor a converter between the battery?

I'm somewhat familiar with Tesla's electric vehicles and that they use AC motors, but I'm completely unfamiliar with EVs that use DC motors. I know that in a Tesla an inverter is required to convert ...
227 views

### PCM1789 DAC direct connection to TPA6138A2 headphone amplifier?

Is it possible to directly connect PCM1789 DAC to TPA6138A2 headphone amplifier? According to datasheet PCM1789 output are differential outputs and the input of TPA6138A2 is also differential inputs. ...
50 views

### Why does one phase of my buildings mains line show a significant amount of voltage (~60V) when it goes down?

The other day one of the phases of our power faulted and the fuse tripped on the power company side. I measured the voltage at 60-65V. Lights were flickering, and some devices kept running (like a ...
27 views

### how can I order motor protectors T150 electrica? [on hold]

I tried so hard to find how can I order this single motor protector from Electrica: T150 but failed to get it on neither fairnel nor on rs-online. as I am repairing my fridge, how do I make sure that ...
1k views

### FDCE flip flop primitive on altera quartus?

I would like to know the altera quartus primitive equivalent to the FDCE flip flop on Xilinx ISE. I think that DFFE primitive might work however I am not sure about the CE and CLR pins equivalency. ...
80 views

### How does such an USB step-up 5V-12V work?

I just bought a cheap USB 5V to 12V step up converter: Surprisingly, it works very well. There is few place for electronic components (maybe in the USB connector?), how can we do a 5V to 12V ...
16k views

### High PCB copper thickness: What are the pitfalls?

We need to carry high currents on a PCB (~30Amps sustained), so we are likely to order our PCBs with high copper thickness. So far we've only used 35 microns (1 oz) in our designs, so 'high thickness' ...
73 views

### Conversion from fixed point to IEEE 754

I am trying to design a simple processor (in VHDL) that takes in its input a real number coded in the fixed point representation in 2's complement (10 bits for the integer part, and 6 for the ...
67 views

### Can I trust in visual inspection to identify LED terminals?

In the figure above, LED A is a regular 5mm LED and the visual identification of its terminals polarity is well known. As you can see, on LED B the anode is identified by the longer leg, but the ...
55 views

### Suppressing sparks when powering motor controller

When I connect a 36V Li-Ion battery source to a cheap eBay DC motor controller, there's a significant spark on the wire, regardless of connected components. Should I: 1) Add capacitors to the input ...
74 views

### Electric motors high volts low amps vs low volts high amps

I have a little electric motor that im trying to use to spin a turn dial. I tryed useing a 5volt 1.55 amp power supply but it just dont have enought power to spin it. I can hook it up to my portable ...
48k views

### Why does a delta/wye transformer make 30 degrees phase shift ?

I'v heard that a delta/delta or Wye/Wye transformers do not make any phase shift. In delta/wye or wye/delta transformers, There is a 30 degrees phase shift between the primary and secondary coils. So, ...
415 views

### State trasnsition diagram for a mealy machine

I created a state Transition diagram for the mealy machine below but I wasn't sure if this is correct. The part that confused me was that s1 has no edges.
65 views

### Strange “step” in i2c plot

I have some errors during debugging I2C chip. I took an oscilloscope and found some strange artifacts on the log: Maybe somebody has a suggestion about such questions? 1. What are these strange ...
38 views

### Looking for gyroscope drift spec in datasheet

The product page of the BMI088 IMU makes the very impressive claim The automotive-proven gyroscope of the BMI088 has an unmatched bias stability of less than 2°/h However, I can't find this claim ...
43 views

### NVG compatibility LED Lights

For an avionics application I need to make a keypanel which has NVG compatible LED lights behind its keys. I am trying to understand how does the NVG compatibility (Night vision Goggles) relates to ...
29 views

### Problems with mbed LPC1768 double precision

I have a motion profile generator which calculates a position 1000/sec. During the decelerating portion of the move, the following calculation is used: ...
25 views

I am novice in PCB component placement and layout. I have just started my career in Hardware design. We have designed a schematic for Data Acquisition System. In our design, we are using three RF ...
311 views

### Two Op-Amp Instrumentation Amplifier - Gain derivation

I came across the following appnote(slyt647) which analyses the two op-amp instrumentation amplifier topology. The gain was found by finding individual gains for each op-amp and adding them in ...
323 views

### Advice for 25-50 Mbit SPI lines - PCB design

I would like to ask some advice for my layout design. I am working on a layout design. The designed PCB will be a Beaglebone Black (BBB) extension card. It is a four layer PCB with the following ...
6k views

### Determining suitable wire gauge for LED-strips (voltage drop)

I am software engineer by trade and a novice in this field, please point out any mistakes in my assumptions and vocabulary regarding this topic. I am designing a lighting plan based around commonly ...
2k views

### Why do we need to use transistors when building an OR gate?

Why do we need to use transistors when building an OR gate? Wouldn't we be able to achieve the same result without transistors at all, just by joining the two ...
789 views

### Bcd subtractor units connections

I'm new in electronics. I'm trying to make a BCD calculator, but I got stuck in BCD subtraction. I got stuck in: how can I connect multiple bcd subtrator units? I'm trying to make a 3 digit calculator,...
228 views

### verilog assign different width input

I have a module in verilog called jtag_sw that expects a 4 bit input. It is a mux. A smaller verison of the code is below as an example. Only 3 signals [0:3] of <...
44 views

### Solar power backed circuit to glow 1W LED

What I have achieved so far: Referring https://www.instructables.com/id/BUILD-A-NOCTURNAL-SOLAR-LIGHT-BULB/ , I have successfully built the Solar Garden Light circuit to glow 5mm led using QX5252F. I ...
73 views

### pH sensor voltage versus pH

I am currently in the process of making an ultra-low power pH captor and I'm running in a problem. The voltage I get from my pH probe does not fallow the Nernst equation (which states that the voltage ...
48 views

### Given a diode circuit and some of its values, how do I find the temperature?

Let's say I am given the following circuit: along with $$dV_p/dT=0.139mV/K$$: Defining V1 the voltage above Diode D1 and V2 the voltage above diode D2 , we use the expression for the current of a ...
27 views

### Touch IC TTP223 is hanged at 5V after some times work

I used TTP223 IC which is operated at 5V , i use touch ic output(When High)to turn on the led and (When low) to dim the led. LED is operated by the External 5V and used only touch ic output as signal ,...
61 views

### What tool do I need for measuring DC power consumption of device over a period of time?

I have a device that's being battery powered and I would like to measure the power consumption over a longer period of time (~24Hours). I want to read both the voltage of my battery and the current ...
33 views

### How to fully open the mos-fet with a low input power ac current?

Sorry for the ugly drawing. The ac source(piezoelectric material under vibration) generate ac current and then rectified by the bridge rectifier. The rectified current will be stored in the capacitor. ...
240 views

### Routh-Array (Control Engineering)

Please see attached slide for a Routh-Array. I'm struggling to see why the encircled element is 4. Rather, according to my calculations it is 0 as the determinant will give zero. Unless I'm doing ...
21 views

### Freestanding bench tester advice for jitter measurement of 50Hz square wave

I am needing advice about which freestanding bench tester to get for jitter measurement of a 50Hz square wave. I prefer a freestanding piece of bench equipment that does not require a sound card or ...
24 views

### HS-1100WP Servo Question

I am getting HS-1100WP Servo. I want to know if I hook them up directly to 12V and turn off the receiver will it drain my 12V battery? Thanks in advance.
7k views

### Critical path for Carry-Skip adder

Can anybody explain why Carry-Skip adder has the same critical path as regular Carry-Ripple adder. My textbook says that critical path occurs when carry is generated in LSB and then propagating it ...
5k views

### What does the “capacitor into resistance” symbol mean?

I can't understand the circled symbol and didn't manage to google it. It looks like a variable resistance and a capacitor. What does it mean?
287 views

### What material(s) are used in IC's as insulating layers between metal layers?

This question and the answers hits close to the topic. One picture shows it as SOD. Silicon-oxide dielectric? I'm aware that around/within the transistor, silicon oxide is grown for insulation where ...
82 views

### Electrical engineering [on hold]

Could someone help me in solving this I am having problem in solving it If I want to convert for example from ohms to k What should I do
85 views

### Filtering current spikes in photodiode transistor selector

I am building a circuit for sensing photocurrent from a photodiode. The diodes are manufactured with selection transistors to form an active matrix and below is a model of a single pixel consisting of ...
36 views

### Understand this surge protector setup

I moved into a flat which has the following electrical setup in the kitchen: Regular looking 4 socket surge protector Combi boiler plugged into surge protector Washing machine plugged into surge ...
622 views

### Lumens specs when buying a flashlight/torch. Why maglite has only 680lm but cheap ones have 900,000?

I am working as a night delivery driver and when its dark and/or rainy it's almost impossible to read many of the house numbers/names I am looking for. I've heard of Maglite and in fact my friend has ...