Datasheets are the primary documentation about components, describing their functionality and electrical properties.

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5
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2answers
56 views

What use is a Zener diode's leakage current spec?

Consider this datasheet for a family of Zener diodes. All of the parts 3V and under have their leakage current rated as some current at 1V. I've seen this is multiple family datasheets, but it really ...
19
votes
4answers
857 views

How reliable is it to use another manufacturer's datasheet of the same part?

There is a part, 1N4148, or whatever from manufacturer A, but the datasheet from manufacturer B is more detailed, has nice graphs, etc. Is in general data for the exact part consistent between ...
5
votes
2answers
90 views

What is the purpose of this bias resistor?

I am unsure what the following statement on page 4 of this application note (Over Voltage Protection Circuit for Automotive Load Dump) means. Resistor R4 provides a small amount of bias to Q2 ...
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1answer
56 views

how to determine the exact value of the capacitor for a particular package using the datasheet [on hold]

how to determine the exact value of the capacitor for a particular package ? In normal case datasheet of the capacitor generally gives capacitor values withing wide ranges like 120 pF to 300 nF for a ...
7
votes
2answers
175 views

Should I indicate that beryllium compounds exist in a device?

Many years ago I built a power supply (an Elektor design) which used a 78HGKC voltage regulator. The data sheet explicitly said not to open the TO3 package as beryllium oxide (BeO) was used for ...
7
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2answers
135 views

Why do datasheets document protocols from the ground up?

I'm reading a datasheets for a component with I2C interfaces. I can recall the same for datasheets of other components in the past. In these datasheets they include a full description of the I2C ...
0
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0answers
25 views

YX805 Datasheet Translation

The YX905 T0-94 package accepts a solar cell, charges a 1.5V AA battery and lights up an LED when it is dark. I don't know how the light detection functionality works -- maybe it is when the voltage ...
0
votes
1answer
65 views

How to translate from data sheet to actual pin function (blank Atmel SAMD21)

I am looking for a way to actually read an Atmel processor (SAMD-21) pin setup; but I am not sure how do you actually get the right info from the data sheet. I did read the pinout, which has names ...
0
votes
1answer
27 views

MC34072 maximum drawn current

How much current can this MC34072 op-amp deliver on the output? Not 100% sure on where to find it in the datasheet.. But is it on page 11 in the pdf document, where the graph shows supply current vs ...
0
votes
2answers
51 views

when modeling a component, do you use the top or bottom view?

I'm modeling a component from this datasheet, they provide both a top view and bottom view of the components seen below, does my pcb footprint represent the top view or the bottom view? This has been ...
1
vote
3answers
73 views

Understanding available frequencies of quartz crystal from datasheet

I would like to make an order of crystals from digikey.com. The crystal product series datasheet is at https://support.epson.biz/td/api/doc_check.php?dl=brief_C-2-TYPE_en.pdf However, I am having ...
0
votes
1answer
48 views

Interpreting the circuit diagram in the dataasheet of TGS2442

In the basic measuring circuit given for TGS2442, in the datasheet Page 2 here can somebody help me in understanding how I can supply both Vc and Vh through the same input. And how can i use the ...
0
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1answer
40 views

No datasheet for SunFounder ADXL345 - can I use a datasheet for the same part number from a different manufacturer?

I'm just getting started with electronics (with Arduino) and have bought this SunFounder accelerometer with part code ADXL345 from Amazon. My problem is I can't find a datasheet anywhere from ...
2
votes
1answer
36 views

Howe to do a sam3x single channel ADC conversion

I have a Sam3x (Arduino Due hardware, but I don't use the Arduino IDE or libraries, and I don't use the Atmel libraries, just the register interface in sam.h). I have multiple pins configures as ADC ...
0
votes
1answer
42 views

ST L4 series datasheet specifications and 1 wire

When you open STM32L476 specification on the The DFSDM peripheral supports (42/232) it says that "Manchester coded 1 wire interface support". Does this means it supports 1-Wire bus like for DS18S20 or ...
0
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0answers
27 views

Can't find TC117HS and RX28 data sheets

I am trying to adapt an RC car to control it with an arduino. In order to do that I am trying to understand the PCB. In the car PCB, there are: one "RX28 TXM ZYX13AA" with 16 pins two "TC117HS ...
0
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0answers
39 views

Li-ion protection circuit: MOSFET connection

I've checked a lithium ion protection circuit and found out that the D1 and D2 terminals from AO8810 are connected: But checking AO8810's datasheet I find that the MOSFET's drains are internally ...
1
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2answers
63 views

finding old datasheets

I am reverse engineering a old circuit board, probably from the late seventies (specifically an Enteron sk-1600-a industrial controller), And I am having trouble finding data sheets. Firstly I am ...
0
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1answer
37 views

Triac Datasheet/Design Questions

1) How do I choose the resistor for a triac? I saw this design in the opto-isolator datasheet that I'm using. I thought I'll just change the resistor value based on the gate characteristics of my ...
0
votes
1answer
71 views

Intel 8259A: why use A0 when there's nothing to address?

I am in the process of writing a driver for the Intel 8259A PIC and using the corresponding datasheet for reference. The datasheet contains a picture of the controller and its connection to the ...
3
votes
1answer
41 views

Intel 8259A: mysterious T bit doesn't fit the pattern

I'm implementing a driver for the Intel 8259A PIC for x86. To do this properly, I am reading the Intel 8259A PIC Datasheet. It is halfway comprehensible even for someone who approaches controller ...
0
votes
2answers
77 views

What is the max current that this circuit can handle?

I'm making a simple project. For me, it is recommended that the output current is 1.5A. But it's OK if it is 1A or 0.5A. For voltage regulator: Datasheet says that the output current is up to 1.5 A. ...
0
votes
1answer
72 views

datasheet dimensions

I am new to reading measurements in datasheet. I am drawing PCB layout of IC LT1761 for my circuit. What I do not understand is what does REF refer to in the datasheet (attached figure)? As far as I ...
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votes
3answers
136 views

Transistor data for values other than the data sheet

I've been reading about transistor saturation to drive 3pcs of 1W LEDs in series from a 12V supply via a TIP31C. I was assuming I would need a Power resistor to balance the voltage drops as the LED ...
0
votes
2answers
88 views

Open loop voltage gain in a datasheet

Here is a datasheet for LM324: https://www.fairchildsemi.com/datasheets/LM/LM2902.pdf It says: Large DC Voltage Gain: 100dB Does that mean the "open loop voltage gain is" 100000? Is "Open loop ...
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1answer
37 views

Determining type of the transistors of an IC from its data-sheet

Does this comparator consist of BJTs?: https://www.fairchildsemi.com/datasheets/LM/LM2903.pdf From its schematic diagram they are drawn like that. But I am not sure if it is the case always. I mean ...
0
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2answers
64 views

Question on LM2577

I have a hard time fully understanding the datasheet of LM2577. I bought this product that has a LM2577 in it and the specifications indicated by the seller that it can have a maximum output current ...
0
votes
1answer
79 views

Upgraded 10 turn potentiometers don't work whereas the original 1 turn potentiometers do. Why?

I bought this adjustable power supply kit and successfully assembled it. I wanted to upgrade the potentiometers to 10 turns so I could have fine control over the current and voltage limits set. Both ...
3
votes
1answer
78 views

AVR external interrupt triggering by the falling edge: for how long should I keep signal low to guarantee triggering?

The question header appeared to bee too long. I'm sorry for that. So I have a schematic generating a short LOW on INT0 pin of ATmega48PA. From the simulation I figured out that the LOW level will be ...
3
votes
3answers
54 views

Finding maximum source impedance for A/D converter (SAM3X8E ARM Cortex-M3)

I would like to find out what is maximum recommended source impedance for A/D converter on Atmel SAM3X8E ARM Cortex-M3 microcontroller. I tried to follow the example of this excellent answer, which ...
6
votes
1answer
80 views

MOSFET power dissipation calculations - Diodes Inc. datasheets

Looking at Diodes Inc. datasheets, I am having trouble following their power dissipation limit calculations for their MOSFETS. E.g. for DMG4496SSS http://www.diodes.com/_files/datasheets/ds32048.pdf ...
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2answers
80 views

MOSFET Heat dissipation question

I'm designing an RGB LED strip driver, and for the MOSFETS for the PWM power switching I'm looking at using the PSMN022-30PL. It has a voltage limit of 30v, and can supply up to 30amps, which is more ...
1
vote
1answer
56 views

How high is the TLC5940?

I've got some TLC5940 PDIP package ICs coming in the mail in a couple weeks or so, and in the meantime I'm designing a couple boards for them. I'm trying to figure out if the TLC is short enough ...
1
vote
2answers
403 views

Can I connect many SX1272 (LoRa) based devices to a gateway?

Simple question: Is SX1272 chip by Semtech capable of sending data to LoRa gateways? I'm a little bit confused about LoRa and LoRaWAN. What is the difference?
3
votes
2answers
97 views

Bridge rectifier - min. required protective resistor

Looking at the datasheet for a MYS80 bridge rectifier, at the bottom it states Min. required protective resistor is 8 ohm. I could not find much information about a protective resistor in regard to ...
6
votes
4answers
935 views

What does “V.A.” mean in datasheet dimensions?

I'm looking at a datasheet for an LCD panel (pdf link to datasheet). I don't understand these two encircled dimensions: What does the acronym "V.A." mean for these dimensions? I have referenced a ...
1
vote
1answer
101 views

Why are properties of components often given at 1 kHz?

The title pretty much sums it up. Aside from DC, why are the properties of components often listed at 1 kHz? I keep hearing that it is a "standard", but why 1 kHz? This seems to be pretty common in ...
1
vote
1answer
212 views

SX1272 - LoRa - What is the minimal schematic (needed capacitors/resistors) to use that device?

I'm interested in SX1272 by Semtech. It's a LoRa modem. I'm not the best at reading datasheets. Maybe it's because of my poor English. I wonder what is the minimum schematic of such a chip? What ...
0
votes
1answer
147 views

Information regarding old AB (Allen bradley) potentiometer JAIN056S102MA

i was looking for information (datasheet) regarding this old potentiometer from 1962 on the internet, JAIN056S102MA type J, 1k-ohm from Allen Bradley and i was not able to find any information about ...
0
votes
1answer
57 views

NJM2072D Application Questions for Audio Detection Circuit

I am building an audio switch with channel priorities. I will use this in car events where we communicate car-to-car on FRS radios. A few of us also use 2 meter amateur radios for longer range ...
1
vote
2answers
165 views

In a circuit with the TI TPS61165, how was D2 chosen?

Looking at datasheet for the TPS61165, I don't see how they chose D2 - it looks like it will only work if the voltage supply is above 12v due to this diode, but the chip's input range is 3-18v. I ...
5
votes
6answers
470 views

Reading dimension in datasheet

This is my first time making pcb layout. I am also quite unfamiliar with datasheets. I am using DS90LV019 (the figure is attached below). What is the actual length of this IC. Does (0.335-0.344)/(8....
1
vote
1answer
65 views

Where are details regarding peripheral configuration for STM32 controllers in datasheets?

I have recently begun working more with STM32 processors coming from the more simple Atmel 8bit variety. The Atmel datasheets are very nicely laid out -- specifically speaking to how they provide ...
2
votes
2answers
202 views

What is LED spatial distribution?

I was going through a 5mm blue LED data sheet and found this diagram in it. Couldn't figure out what it is.
1
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1answer
42 views

Currents confusion in a JFET datasheet

I am analyzing a JFET. The datasheet has both information about the currents Igss and the maximum of Ig. I know that the Igss is a the reverse current in the PN junction but I can't explain myself ...
0
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1answer
44 views

Input Impedance Question

As I look at the Datasheet of a differential amplifier for input impedance, i see below statement. 0.8||2 for Differential. 0.4||2 for Common mode. What does GΩ||pF mean?
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1answer
64 views

Hashtag Beside Pins names [duplicate]

What does Hashtag (#) means when it's added beside some pins names in datasheets..like WE# in the flash memeory pinout or RI# in RS232 FTDI datasheets??
1
vote
1answer
103 views

Voltage follower with a RF signal

I have a RF signal up to 50 MHz coming from a VCO which I want to use on a different impedance circuit. Without any adaptation the signal go down quickly when i raise the frequency because my load is ...
2
votes
1answer
143 views

Need help understanding how to calculate the R value for LD1117

I am really trying to understand how to use adjustable voltage regulators such as the LD1117 sold by sparkfun. I had a look at the datasheet they provide in the product page but it points me to a ...