Questions tagged [reference]
The reference tag has no usage guidance.
62
questions
1
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1answer
41 views
Question about feedback in a current reference
I'm studying the following Vbe-based current reference:
The author of my book says:
Observe that the circuit has two feedback paths around the gain stage. One positive, the other negative. ...
0
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0answers
31 views
Question about current reference
I'm studying this thermal-voltage-based current reference:
The working principle is simple: M1 and M2 form a current mirror which generates two equal currents I1 and I2 (assuming M1 and M2 equal). M4 ...
2
votes
1answer
62 views
Self Biased Current Reference
I'm studying this circuit:
The author of my book says that the purpose of this circuit, called "Self Biased Current Reference", is to generate a current almost independently of the supply voltage. He ...
0
votes
1answer
53 views
STM32F429ZI reference voltage
I want to use the full output resolution of DACs (12bit) in the range of 0-1 Volt (and not in the range 0-3.3 Volt). I see there is a pin VDD in this board (STM32F429ZI), please help me to understand ...
0
votes
1answer
54 views
Series voltage reference output voltage
What is output voltage of series voltage reference IC (for example MAX6100) when input voltage is below minimum input voltage? Is it zero volts, or something else?
Didn't find answer to this from ...
0
votes
1answer
76 views
Wheel heading using PWM
I have a general question which im not sure how to implement.
Suppose that a car is driving on a straight road and it starts doing some maneuver.
Due to this maneuver the driver moves the wheel ...
2
votes
1answer
58 views
Selecting the equipment with the optimal 10 MHz reference
In a larger testbench I have 5 synchronized instruments (signal generators, ARBs, VSAs etc). I am trying to decide which instrument to take as "master". I rule out the older/cheaper parts (Tektronix ...
2
votes
2answers
295 views
10 MHz reference distribution (daisy chaining vs. BNC tees vs something else)
10 MHz is the quasi-standard for reference clock in measurement equipment. Most boxes have "REF in" and "REF out" or "10 MHz in"/"10 MHz out".
In my case, I have a measurement setup consisting of an ...
2
votes
3answers
189 views
Create small variations in voltage for opamp reference pin
Hello and thanks beforehand.
I'm designing a circuit to measure 4 wheatstone bridges using 4 Analog Devices AD8422 in-amps. Now, i'm feeding the AD8422 output to a 3.3V ADC, so i'm offsetting the ...
0
votes
1answer
64 views
AREF Voltage same as VDD but through a reference IC
My project has 9V and 3.3V on the board. I would like to use a precision voltage reference IC for the analog reference on the MCU (MCU powered by 3.3V).
The precision of the voltage reference IC is 0....
13
votes
3answers
2k views
Copyright of reference designs?
I have been reading a design guide by TI which provides full schematics for their reference design seen Here.
There is copyright stamped all over this document as seen below. I don't plan on using ...
0
votes
2answers
182 views
the voltage output and resistance of a potato
For an undergrad lab experiment on noise analysis in various electric power suppliers, I constructed a battery from a potato with Cu/Zn electrodes and measured the outgoing voltage. Now I want an ...
1
vote
3answers
383 views
How an op-amp determines its output without a reference point? [duplicate]
I was struggling to understand how an op-amp determines its output without a reference point.
The output of an op-amp is A * (Vni - Vi)
Then let's say we have an inverting op-amp with a gain of 1000,...
0
votes
1answer
55 views
Measuring PSR of a current reference chip
Some Background:
I'm designing a test board to characterize noise and PSR of a multiple voltages(1V) and currents(1uA) reference IC. The chip has a single voltage source. I use ultra low noise MUX ...
2
votes
1answer
66 views
A mechano-electro-magnetical control circuit
I came up with the following mechano-electro-magnetical control circuit. The system as depicted here is in equilibrium, i.e. the upper spring s1 is relaxed , the upper circuit is closed (C1 producing ...
0
votes
2answers
104 views
FPGAs and deep learning curcuits? [closed]
There are examples for so called neural computing like SHAVE based Myriad2 chip, basically or at least part of it, a VLIW (under 30nm and 1-2 W)
Now, does it make sense to design a neural net on an ...
5
votes
1answer
452 views
What do decimal/alphanumeric suffixes after a slash mean in a schematic cross-reference?
I'm looking at a circuit diagram for the ChipWhisperer, which is a tool for power analysis and glitch attacks. You can grab the full circuit schematic as a PDF, but here's an excerpt:
What do those ...
5
votes
4answers
2k views
Capacitor after Voltage Reference “for stability”
I've got a lot of experience with rather "low-level" electronics (resistor networks, passive filters, basic op-amp circuits) and some experience with higher-level stuff like micro-controllers, but I ...
3
votes
1answer
353 views
How to connect a diy audio signal to my “expensive” audio interface
I'm a hobbyist and after some experimentation (around 4 years) I want to connect my signals I create on the breadboard to my expensive audio interface. Until now I was using the "mic" input on my ...
3
votes
1answer
3k views
MOSFET Temperature coefficient
I'm reading a paper by Guillermo Serrano and Paul Hasler, A Precision Low-TC Wide-range CMOS Current Reference, IEEE JSSC Vol 43, no 2, Feb 2008. Link to paper - requires subscription to IEEE Xplore ...
1
vote
6answers
189 views
LM385Z-2.5 in series with voltage divider - voltage reference problem
I'm doing a simple circuit using LM385. In THEORY voltage measured on cathode of D2 should be 5V. And it is so, if R2 and R3 are not present in the circuit. So voltage divider from R2 and R3 across ...
0
votes
1answer
48 views
Reference of component
I´m trying to repair my lock control in my car. And this board seems like the problem, so I want create a new board (exactly the same) based on this. But I facing a challenge:
I cant determine what ...
1
vote
1answer
154 views
How to learn designing electronic cicuits? [closed]
This is a soft question. I have completed my engineering in electronics discipline and unfortunately I still don't have proper idea of designing electronic circuits. But anyhow I want to clear this ...
0
votes
0answers
208 views
The precision of internal voltage reference in PIC
I am designing some circuit with PIC16F18345 and I need some voltage reference (±0.5% or better). I can add some external reference or use built-in internal voltage reference in that MCU (that means ...
0
votes
1answer
441 views
Reference circuit design for UART on GSM module
I'm designing a small development board (from schematic design to PCB), centered around an ATmega32U4 MCU, and a Quectel M95 GSM module. I'm using the M95 Hardware Design Manual (http://www.quectel....
0
votes
1answer
53 views
LL2263-14 ADC input range question
I'm using LTC2263-14 14 bit pipeline ADC in my application. However, I'm completely confused regarding the input voltage range, reference voltage etc. It has a differential input with an internally ...
3
votes
2answers
299 views
Active resistor for gain Control for reference pin in instrumentation op amp
I'm using an instrumentation amplifier (AD8421 from analog device) to amplify very small signals in magnitude from 20uV to 500uV max. the problem I have with this is that the signals might have some ...
0
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0answers
161 views
The Art of Electronics exercise 1.19 [duplicate]
I'm reading The Art of Electronics(3rd), and I'm just stuck with exercise 1.19. Here is the question:
Explain why L∝n² for an inductor consisting of a coil of n turns of
wire, maintaining fixed ...
1
vote
2answers
258 views
Voltage reference sampled by ADC (12 bit) gives value that is off by more points than other measurements
I am using the TI REF3020 voltage reference (2048mV) in combination with a microcontroller in order to have a reference for voltage measurements.
The microcontroller is powered by 5V (5.00V), the ...
1
vote
1answer
84 views
Help me check the values for capacitors in a reference design
I have the following circuit diagram from documentatoin for an MC34167 which I'd like to use in a project.
Am I correct in assuming the capacitors are all in pF? which would give me:-
330pF
4700pF
0....
0
votes
3answers
79 views
auto-recalibration of a power supply through something stable over time? (thought experiment) [closed]
Highly accurate instruments with a calibration are quite expensive, and anything electronic will tend to change over time. The effects of heat and oxidation, and perhaps changes in the material due ...
1
vote
2answers
238 views
Instrumentation Amplifier REF pin maximum voltage
I'm a spanish engineer student doing my end-of-degree project. I need to remove the offset of a strain gauges bridge and i'm trying to make the calibration automatic, using a DAC (digital to analog ...
1
vote
1answer
271 views
Precision shunt regulator failure behavior
I'm working on a project that uses an LM4040 precision shunt in order to obtain a 2.5 V reference voltage (in particular, I'm using the LM4040-N-25). My circuit is similar to the one shown below (from ...
5
votes
2answers
573 views
Why is it a bad idea to divide reference voltage only with resistors instead of using an op-amp buffer?
I'm planning on shifting the output of an AD8226 instrumentation amplifier by 'about' 0.5 volts using a 2.5 v precision reference and a voltage divider. According to the datasheet this is a bad idea ...
1
vote
2answers
575 views
What component is a VZ reference designator for
The board I'm looking at is a modem board from a fax machine.
There are 2 identical components labeled VZ1 and VZ2 on the board, both components have F175 on the face and have 2 SMC leads.
One of ...
1
vote
1answer
196 views
How to simulate adjustable 'negative resistance' with active components?
I'm building a decade resistance box using 2W resistors, from 10x1M ohm to 10x0.1 ohm. However, due to some contact resistance, the 0.1 to 1 ohm resistance will likely turn out to be ~1.1 ohm to 2 ...
0
votes
1answer
71 views
Reference clock output conditioning?
I have designed a GPS disciplined oscillator.
It's performance is nominal for the design, but the question I presently have is about conditioning the output for presentation to a front panel BNC jack....
0
votes
1answer
71 views
Versatile input termination / translation for reference clock?
I've got a microcontroller I want to clock from an external 10 MHz reference. I'd like the reference input to be as versatile as possible. At the moment, my reference is an LVCMOS square wave, but ...
4
votes
3answers
2k views
What are some good Electrical and Electronics blogs worth following? [closed]
This is a soft question. I am newly admitted to Electronic and Electrical engineering . Under this branch there are multiple domains from which I may work in one of them in the future.
For knowing ...
0
votes
2answers
73 views
How to quantify the health of an electronic appliance according to its power consumption? [closed]
Is there any ways to quantify the health of an electronic appliance according to its power consumption?
1
vote
1answer
549 views
PIC18F Internal reference
I am currently in the middle of migrating a project from PIC16LF1947 to a PIC18F87K22 as I am in need of extra GPIOS and the PIC18 part fits the bill. There is one thing that is nagging me right now ...
0
votes
1answer
478 views
“LB” component reference designator
I'm doing a bit of reverse engineering on my Das Keyboard Model S Ultimate. I'm beginning to develop a pretty good understanding of the circuitry, but I am confused about one type of component on the ...
1
vote
1answer
259 views
Need Programmer's Reference Manual TI Stellaris LM4F120H5QR
Just searched the Texas Instruments' website for LM4F120H5QR Programmer's Reference Manual
Found nothing.
Example...
While stepping through some code, I come ...
0
votes
1answer
194 views
Hardware reference design for a phone [closed]
I want to make a simple box with one button. Pressing the button will send a SMS Text message to a preprogrammed phone number.
I have not designed a phone hardware before so looking for some simple ...
0
votes
2answers
580 views
Can I adjust the volume of a DAC using PWM?
Here is a circuit that allegedly converts PWM into a precision voltage reference:
circuit http://dangerousprototypes.com/wp-content/media/2012/03/64750.jpg
I am thinking about feeding that reference ...
1
vote
2answers
3k views
AD620 in-amp reference pin
I have a weighing scale project using a 200kg load cell with a rated output of 1mV/V. I used 5V as excitation voltage and an Ad620 in-amp for my amplifier. I only need atleast the 0-100kg so I only ...
0
votes
1answer
466 views
Precision voltage reference for load cell and ADC
I want to know what could I use to have a stable 5V excitation voltage for my load cell(wheatstone bridge) which I could also use to have a stable 5V reference voltage for my arduino adc. Would a ...
1
vote
2answers
1k views
Eagle cad replace command using command line
I am using Eagle Cad and changed my libraries to another folder. I needed quicker access. Now I have to update my components in my schematic and wanted to use the replace command from the command line....
1
vote
0answers
321 views
Frequency locked loop for input jitter rejection
I have an application where I want to multiply from a xtal oscillator
at 32KHz to a system clock of 40MHz. A standard PLL isn't going to do the
job, because the 32KHz jitter is measured in ns. Since ...
0
votes
2answers
131 views
What should I use for a 3.3 voltage reference that sinks maximum of 1mA?
I am in search for stable and precise 3.3 voltage reference IC. I am using it for the temperature sensor application which only sinks 1mA at max. Can someone suggest me a best component/IC for this ...
