Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [split-supply]

24 questions
18
votes
7 answers

How make a dual +-12V supply from a 24V SMPS

I'm trying to power a home-made load cell transmitter using a 24V single SMPS. I need to make +12, 0 and -12 Volts that are capable of 50mA. I wish to power multiple channels of opamps and bridges. I don't have much budget and availability of…
Ohbhatt
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13
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9 answers

How does an op-amp know where ground is?

Although I've been working with op-amps for a while, the following question never occurred to me before today. Consider first the op amp on the left (A). The negative terminal is connected to ground, and a small voltage \$V_d\$ is applied between…
MGA
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6
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5 answers

How do you calculate negative and postive voltages in a grounded circuit?

This may be a vintage question, I'm not sure. I am self-studying electronics using some old books and came upon the problem below from "Basic Electronics" by RCA Institutes, 1965. The book is fantastic, but some of the terminology and tech is…
decuser
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3
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2 answers

Op-amp: Why does single-supply have better PSRR?

The OPA2810 datasheet mentions: An additional advantage of configuring an amplifier for single-supply operation is that the effects of PSRR are minimized because the low-supply rail is grounded. This description is unclear. I guess this is because…
curlywei
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1 answer

Two transformers with common ground (Split supply)

When and where you can have a common ground? In this case between 2 different transformers. The initial goal is to have: One Ground -15 V +15 V +12 V The split 15 volt supply will be used for driving a few op amps and the 12 volt supply will be…
Lex Geurts
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7 answers

Why doesn't current flow to ground in some circuits?

Given the circuit drawn below, why doesn't current just go from the positive terminal of the battery straight to ground as in A. but, rather it goes round and round the circuit from the positive terminal of the battery through the loads and back…
decuser
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3 answers

How does this voltage divider work?

I'm trying to understand how this voltage divider works with an NPN transistor in it. If there were no transistor, V_OUT = 10.2 * 5.1k / (5.1k + 1.8k) = 7.54V Reference to ground 7.54 - 5.1 = 2.44 V It makes sense that the transistor would add some…
timsweeney7
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2 answers

Single rail power to balanced

EDIT: I built up the circuit shown below. I had the power transistors lying around, as they're a type used for class B audio amps, and they're dirt cheap on the "jungle river" website--about 12 bucks for five pairs. Without heatsinks (which clearly…
Toby Eggitt
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1 answer

Standard approach for a split power supply ADC?

I'm currently working on a project that will incorporate an AD7124-8 ADC, which as far as I understand can accept true bipolar inputs when provided a split supply. I tried to dig around for an app note or reference design from AD on this, but…
Sensors
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1 answer

Are there commercial split +/-5V DC power supplies?

I have a custom amplifier board that works with some scientific equipment. There is a molex-type connector on the PCB that requires +5V, -5V, and ground (3 pins). When I try to search for a +/- split power supply, I can find lots of do-it-yourself…
thegreatemu
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3 answers

Split supply from 24V power supply using uA741 opamp

I want to connect a 0-3V analog sensor output to the 0-10V analog input of a PLC. In order to avoid losing resolution, I have amplified the sensor signal using a non-inverting amplifier circuit (based on the old uA741) so I get the full resolution.…
bardulia
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2 answers

Parallel split rail supply with only positive regulators

I'm designing a +/-12V split rail supply for a eurorack (modular) sythesizer. I was adviced to put a pre-regulator block at a higher voltage a connecting to it several point-of-load regulators. Because of the transformer I have, I was required to…
Jonas Daverio
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1 answer

Split power supply for battery simulator circuit is getting hot while connected to a battery charger

In order to test a Li-Ion battery charger on our board (the BQ24074) I built a battery simulator circuit which was initially designed by TI. The circuit "pretends" to be a battery and can provide different voltages to study the behaviour of a…
Neki Dzemaili
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0 answers

Multiple grounds errata corrige?

simulate this circuit – Schematic created using CircuitLab Here is a thought (hopefully) to my grounding/shorting problem (Multiple ground). Would this circuit work being fed by the li-ion cells to obtain an isolated +-3.7V? What kind of…
Status Re
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Will asymmetric loading of my split rail supply cause problems?

I plan to use a MTU1D0509MC Series isolated DC-DC converter to power an in-amp and supply bias current for a resistive sensor. I couldn't find anything in the datasheet about asymmetric loading: Datasheet The supply is rated for 1W and I need about…
griffin175
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