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Interfacing with 0..-2v Sensor using ADS1115

I'm designing a circuit to interface with a sensor that operates on a ±12VDC power supply and outputs a signal between 0 and -2V. I plan to use an ADS1115 ADC for reading this signal. Circuit Design: ...
MJerjawi's user avatar
2 votes
1 answer
185 views

Measuring a voltage signal ranging from -2 to 2 volts into a 16 bit ADC circuit

I'm trying to read a voltage that represents a signal from a sensor. This signal can range between -2 volts to +2 volts. I wanted to read this signal to log it, but most ADCs (including ones on an ...
gjossep's user avatar
  • 23
4 votes
1 answer
374 views

What is negative PWM (with switched ground)?

I was reading documentation about flaps control unit for experimental aircraft, and I found, that indicator LEDs on device are dimming by something they called "...
marcel3032's user avatar
0 votes
1 answer
143 views

Inverting DC voltage [closed]

I want to invert a DC voltage of 12V to -12V in the simplest way possible, since this circuit will be used in a bigger rad-hard project. I cannot use directly a DC/DC converter or any other ICs, but ...
Francesco Poziello's user avatar
0 votes
1 answer
80 views

Multiple negative analog signals to positive signals [closed]

I have multiple analog DC signal of sensors each connected via a coax cable. The outer layer of the coax cables needs to be grounded into a metallic wall for EMC capabilities radiation safety, thus I ...
R_N's user avatar
  • 3
3 votes
2 answers
754 views

Which side is the capacitor negative on this board? (IO/10 marking)

I removed a capacitor (C1 (400v/15uf) - highlighted in the picture) from this board to test on another board and now I want to put it back but I can't figure out the polarity. The traditional symbol ...
ExpectZomibesBy2020's user avatar
0 votes
1 answer
116 views

Regulating negative voltage with a positive LDO

I have Traco TEN 5-1221 to generate positive and negative 5 volts. I need to further lower the voltage to 1.5V. I decided to use a BA15JC5T for positive 1.5 volts. Is there a way to use it for ...
Kurt Müller's user avatar
0 votes
1 answer
134 views

Voltage of electric motor

What is the range(min value and max value of average motor) of a voltage in an permanent magnet synchronous electric motor? I am current working on a dataset of Permenant Magnet Synchronous Motor(...
Ameya Hujare's user avatar
1 vote
1 answer
828 views

Van conversion hookup point AC Earth to chassis negative

I'm helping my brother convert his van into a camper and installing solar panels, a leasure battery, and hook-up point, but I'm slightly confused. I've been working on the hook-up and loads of things ...
Martin Barker's user avatar
1 vote
1 answer
107 views

LMV431 to generate negative voltage

can someone show me how to use LMV431 to generate -1.24 V from -5V? below is how I use it for positive. Thank you
Kurt Müller's user avatar
0 votes
1 answer
73 views

How to make this homemade enable? Need the OUT voltage to become -6 V when the enable voltage is turned on to 3.3 V

I don't need to be using a MOSFET, just figured that would be the way to go.
Jespy's user avatar
  • 1
1 vote
0 answers
207 views

Is it possible to share a common 0VDC (negative) between three DC switch mode power supplies - when two of them are in series?

I have a system that needs a 96VDC and 12VDC feed to operate. I have a pair of Meanwell RSP-3000-48 power supplies tied together in parallel to supply 96V and a single Meanwell HLG-240-12 supplying ...
Dion B's user avatar
  • 11
0 votes
0 answers
93 views

Pull negative battery to ground with MOSFET

I have an input signal that goes from +10 V to ground and I want use it to pull the node "A" to ground. The current will flow towards node "A" I was thinking using a NMOS, with in ...
Trame9000's user avatar
0 votes
2 answers
646 views

The minimum (negative) value of the exponent in decimal

I am learning computer architecture and organization. I am stuck in the following question. Can someone please help me? For a floating-point representation with 35 bits in the mantissa and 15 bits in ...
Anshul Gupta's user avatar
0 votes
1 answer
90 views

Are these 2 equations some of general formulas of infinitesimal length?

Given below. \$x\$ is a variable. \$r:=\text{resistance between the nodes A and B}\$ \$l:=\text{length of the resistor }r\$ \$\rho:=\text{resistance per unit length of }r\$ \$\frac{1}{\rho'}:=\text{...
electrical apprentice's user avatar
4 votes
1 answer
111 views

Generate +/- voltage outputs using two boost converters?

I am working on a project to power some audio equipment that requires +/- 15V DC. Output current load is about 250mA, maximum. I am wondering if there’s any reason I couldn’t create this using two ...
seagull48's user avatar
1 vote
2 answers
301 views

Coaxial cable in IT Earthing System

We are developing a shipboard system which needs to be connected in a IT network (Unearthed neutral). In order to comply with this scheme we need to avoid negative-grounded, as all the metal ...
Dhargon's user avatar
  • 11
0 votes
1 answer
69 views

Op inverting amplefier circuit

i am using the LM741 amplefier i want to invert a negative voltage (-10V) to positive voltage (1V), my problem is : i dont get the 1v DC at the output. i get an ac signal at my oscilliscope. and i ...
hos's user avatar
  • 61
2 votes
1 answer
213 views

Help explaining negative (ground) power connection through TV setup even though wire not connected?

After attempting to use a power inserted for the OTA antenna I discovered an unexpected problem. The inserter is powered by an UnGrounded Ac/DC adapter (Wal-wart as they are often called). All worked ...
user2860253's user avatar
0 votes
0 answers
28 views

Switched-cap/charge pump only way to generate negative rail voltage for op-amp?

I need to design a daughterboard that gets mounted directly to a piezo mic to condition the signal before transmission. Part of the conditioning is a full wave rectification. Thus, as you'd expect ...
Matt's user avatar
  • 201
2 votes
3 answers
240 views

Frequency Conversion Product Lower than 0 Hz (Negative Frequency?)

If I have a bandwidth of frequencies from 200 to 500 Hz made from cosine waves and I mix this with a oscillator at 400 Hz which is also a cosine wave, the mathematics of conversions show that I will ...
Natalie Johnson's user avatar
0 votes
1 answer
830 views

'Inverted' voltage follower with an opamp

I'm trying to figure out how I can achieve an 'inverted' voltage follower. That is if I'm feeding 1V I output -1V, if I feed 2V, -2V etc. I'm only going for positive tension to negative, I have +15 ...
brunobhr's user avatar
  • 150
0 votes
0 answers
130 views

10mA inverting charge pump

I have limited knowledge of switch caps voltage inverters and charge pumps. I need to generate -2.5V in my system capable of sourcing about 7.5mA. I have MCU and two rails 3.3V and 5V. So far, I ...
Wintermute's user avatar
2 votes
0 answers
1k views

MOSFET Gate driver - negative voltage with Zener circuit

I was reading about minimizing MOSFET switching loss when I came across an article by Texas Instrument on how to use negative voltage, instead of ground, to faster discharge MOSFET gate capacitance. ...
bstack's user avatar
  • 51
1 vote
2 answers
2k views

Can a resistance be negative?

I have to calculate the value of a resistor so that my circuit has a certain equivalent resistance. This is the circuit, and here are the values: ...
F. Iván's user avatar
  • 113
2 votes
1 answer
4k views

Verilog: Posedge sensitivity vs. If statement in Always block

I have recently completed a design that had run into timing issues (negative slack). The modules that were found to be troublesome, from the timing reports generated in Vivado 2017.4, are these ...
dby's user avatar
  • 43
0 votes
1 answer
323 views

Negative 15V supply from 24Vdc

For my application I have two AD633 Analog Multipliers that need a ground referenced +-15V supply. I have a 24VDC and a 8 VDC supply to use, but i would prefer to use the 24V supply. I've looked at ...
Bruno Carreira's user avatar
2 votes
1 answer
1k views

Why MOSFETs in Battery Management System are connected to negative terminal?

I have seen that the MOSFETs and current shunt resistors are connected to the negative terminals of the battery or the BMS. Is there any specific reason for this? Why aren't they connected to the ...
launchin2space's user avatar
1 vote
2 answers
467 views

Getting negative energy in a coil (RLC-circuit) after opening the switch

I've the following circuit: simulate this circuit – Schematic created using CircuitLab The switch was 'forever'closed and a certain time \$t=0\$ I open the switch. I tried to find the energy ...
Topil's user avatar
  • 13
0 votes
0 answers
1k views

Negative voltage supply

I've been trying to make a active load that would use a very small resistor, around 10mOhm as a shunt resistor. I've figured out how to make it, it's a common circuit, however since I need to use ...
CrtSuznik's user avatar
0 votes
1 answer
125 views

Get negative control voltage for a AS3310 chip

I'm trying to use a AS3310 chip to generate an envelope from a trigger/gate signal. The AS3310 expects for the ADR (attack/decay/release) control voltage 0 to -5V - for the S (Sustain) 0 to +5V I ...
m_c's user avatar
  • 15
0 votes
1 answer
626 views

Designing two stage CE amplifier with negative feedback [closed]

I'm trying to design two stage ce amplifier with negative feedback using 2n2222 transistors. The circuit must have certain voltage gain, Rin, Rout, Vcc, low and high frequency filter. This is the ...
J Jon's user avatar
  • 1
0 votes
1 answer
86 views

Op amp with feedback

simulate this circuit – Schematic created using CircuitLab How to calculate Iout(current flowing through RL) of this circuit? All Resistors are of same value except the load resistor. Let the ...
Ravi Teja 's user avatar
1 vote
0 answers
589 views

Magic Eye Tuning Tube Variable Negative Voltage

I am thinking about several applications of magic eye tuning tubes as display pieces and had a question about their operation. I have attached a sample circuit from a datasheet for an EM84 tube. I ...
Efram Goldberg's user avatar
0 votes
2 answers
343 views

Negative gate SCR

I've accidentally supplied the gate of an high power phase control thyristor (Vdrm=5200V and It(rms)=6500A) with a negative current (about two times the trigger current and four times the trigger ...
Maris's user avatar
  • 15
1 vote
2 answers
146 views

Operational amplifier and negative feedback

Let's consider an op-amp. In every book I've read till now, it is said that if we have: negative feedback finite output then we have: Vout = A * (v2 - v1) --> (v2 - v1) = Vout / A If A is very ...
Stefanino's user avatar
  • 616
1 vote
1 answer
916 views

What defines the sign of transistor rating values?

Here for example I have attached excerpts from two general purpose PNP transistor datasheets. One of them has negative values, other one positive. I would like to understand what defines these values ...
stardust's user avatar
  • 218
0 votes
1 answer
624 views

LED indicators for 2 Positive voltages and 1 Negative

I have a seemingly simple question but I am getting stumped. I have a power supply providing +12v +5v GND and -12v. I would like to have an LED for each input voltage showing that they are working ...
Ashley Reid's user avatar
-1 votes
2 answers
743 views

Generate negative reference voltage

In my current design, I need to include force measurement. A301 sensor is selected for this. Now, in order to be able to have analog voltage proportional to the force applied, I need to have negative ...
bojankoce's user avatar
0 votes
1 answer
1k views

negative binary representation and 4 bit BCD represenation are similar

While representing negative numbers in binary we use MSB as sign indication.In BCD we use 4 bits to represent numbers 8-15. How does a device(ex:computer) decide whether its a negative number or a ...
Siddharth's user avatar
0 votes
1 answer
1k views

Applying negative voltage to CMOS chips

I have a situation where it's possible a negative voltage may appear on the power supply rails driving CMOS chips. The negative voltage will be very limited in current, fed through a resistor. The ...
Foxie's user avatar
  • 221
0 votes
1 answer
854 views

Calculating power supply current output

I have a 15V power supply powering 2 Dc/dc converters that are the same. The converters are connected so that the outputs are 10V and -10V (the - terminal of the 10V converter is tied to the + ...
user177887's user avatar
1 vote
0 answers
108 views

Battery life and negative current

I am working on a battery powered project. With a multimeter I've been measuring current on the "positive" side of a module and observe 5μA. However I thought to measure the "negative" side and was ...
RamblinRose's user avatar
1 vote
0 answers
62 views

Apply positive and negative voltage to component using single power supply [duplicate]

I have an electromagnet and a 12V power supply. I would like to apply +12V to the electromagnet at some times and -12V at other times. My current thought is to use four transistors (two NPN, two PNP) ...
randomhead's user avatar
0 votes
1 answer
559 views

Function Generator - Signal without Neg or Gnd reference

I have a new PC based function generator (very cheap), and an old BK Precision function generator. The old BK Precision can output a signal without the ground or negative reference lead from the BNC ...
MaxHenry's user avatar
0 votes
5 answers
56k views

When do I connect to negative terminal or ground?

Easy question (or at least I think). I've installed a siren in my vehicle which calls to pull power direct from the 12 volt battery. I currently have the circuit completed by connecting to the ...
Justin Collins's user avatar
2 votes
2 answers
628 views

Analysis of Negative Input Resistance Op Amp

simulate this circuit – Schematic created using CircuitLab I'm having a difficult time analyzing the circuit shown and would appreciate some help. I'm just curious in order to get better at op ...
M. Mocha's user avatar
0 votes
3 answers
112 views

Connection of dusl 12v NiCd battery packs [closed]

I have the 12v battery (it is actually 10 Ni-Cads in series), and, of course, it has a red wire coming from "+" and a black wire coming from "-". However, on the schematic I am confused about whether ...
Fairbro's user avatar
3 votes
2 answers
11k views

Where is the positive and negative on an antenna?

What I am wondering is how to build an antenna. Upon unscrewing my telescopic antenna from it's base, I see only a metal screw base, nothing more. The F Connector has a positive and negative (or ...
ToastHouse's user avatar
0 votes
1 answer
728 views

Negative charge pump problem

I have an 18V 1.5A mains transformer (outputs around 30V peak with no load at 50Hz) followed by a full-bridge rectifier and a filter capacitor: (there would be a schematic here if SE allowed me more ...
fishgi's user avatar
  • 11