Answer by Lundin for Soldering problems, is it me
What wattage is necessary?Doesn't really matter unless you do professional soldering. What you need is a temperature controlled iron. A good beginner temperature is somewhere between 250-300°C....
View ArticleAnswer by Lundin for ATMEGA328 out of memory, but avr-size reports I still...
Check out my answer below What resides in the different memory types of a microcontroller? The linker is able to diagnose the memory use of flash (.text + .rodata) and static RAM (.data + .bss) at...
View ArticleAnswer by Lundin for Machine Directive has high priority than Low Voltage...
They are not really overlapping so you need to conform with both, assuming a supply of >50VAC or >75VDC.The machinery directive addresses things like functional safety, operator hazards,...
View ArticleAnswer by Lundin for STM32 HAL_CAN_ERROR_PARAM;
Your time quanta (tq) settings do not make any sense at all. Your tool appears to call tq "time". ("How many 'time' do you want?" thx ST great tool...) The tq settings might not be the only problem in...
View ArticleAnswer by Lundin for Please review my PCB design for 6502 circuit
Ignoring that the schematic doesn't quite match the layout in many places, then:Major remarksYou should have a more careful ground layout, start with it. Place for example all GND traces on the solder...
View ArticleAnswer by Lundin for How to design short circuit and reverse polarity...
Short circuit protection for outputs is conveniently handled by using "smart" MOSFET drivers with built-in current limits, short circuit protection, temperature protection etc etc. Examples....
View ArticleAnswer by Lundin for Why do manufacturers label differently seemingly...
The way the electronics industry is supposed to work (but rarely does):When you buy a component from a supposedly reputable component vendor like Arrow, Avnet etc, they are supposed to keep tabs on...
View ArticleAnswer by Lundin for Assistance identifying an op-amp marked "H2P IFA"-...
Could be Analog Devices ADA4896 series. Single channel rail-to-rail OP. Marking H2P. Ground on pin 4, supply on pin 7 (pin 8 is a /Disable pin and could be tied to Vdd probably). And this might be what...
View ArticleAnswer by Lundin for Reasons to use combinations of resistors (parallel or in...
Examples from the real world:Sticking to the "E series".The calculated component value you need might not be available in one of the standard "E series", which in turn means that it might be more...
View ArticleAnswer by Lundin for Is Modbus suitable for motion control positioning?
TCP/IP based systems are not real-time systems. There are no guarantees that packets will arrive in a timely manner, or at all. Therefore it is considered unsuitable for real-time control. As for the...
View ArticleAnswer by Lundin for Soldering iron tip gets oxidised
with the occasional steel woolDon't do that! It's likely what's killing your tips. Anything that might scratch the surface should not be used. That includes steel wool, sandpaper, files etc.Is there...
View ArticleAnswer by Lundin for Is soldering flux absolutely necessary for lead-free...
It's kind of hard to find any decent solder for hand soldering without a rosin flux core. Also I wouldn't really call "SOIC, SSOP, SOT" fine pitch, these are typically 1.27mm/0.05'' or larger. You...
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Answer by Lundin for MCU Input ESD Protection + debounce
A general-purpose input circuit for industrial applications might look along the lines of this:simulate this circuit– Schematic created using CircuitLabTVS rated according to what you expect, typically...
View ArticleAnswer by Lundin for CAN bus HW testing (STM32MP157CAA)
@Attie has posted a good answer, but just to clarify some details:Loopback mode is used in the early development phase when the programmer wants to test things before even the evaluation board with...
View ArticleAnswer by Lundin for GPIO controlled CAN bus termination technique
These parts likely are too slow to be used, up to 6ms switching time.Compare that to your baudrate and count how many error frames that may get sent during that time, enough to put the part in error...
View ArticleAnswer by Lundin for Is external ESD protection needed with the MAX3051?
Regarding external ESD protection: it depends on your requirements. You don't mention them, so we can't answer that. Human body model is for humans sticking their fingers in some connector. There are...
View ArticleAnswer by Lundin for STM32 for loop slows down code too much
Speaking about performance without mentioning how you compile the code is kind of pointless. It shouldn't be a mind-blowing realization that optimized code runs faster than code with optimization...
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Answer by Lundin for How to control 0-5V in 5 steps? (1V, 2V, 3V, 4V and 5V)
A rotary switch + resistor ladder will work. A rotary switch being a selector switch where only one position at a time is selected, mechanically. So note that the switches in the below schematic is...
View ArticleComment by Lundin on What are the limits for broadband (BB) and narrowband...
@Hari Quasi peak is some EMC test term where a peak detector is used together with some manner of damping, I'm far from an expert at this so wikipedia can explain it better. For the average electrical...
View ArticleComment by Lundin on UART and RS422 Interfacing
@Justme The question is clearly about UART since it says so. I was making an example of when it might be justified to route a UART signal to GPIO.
View ArticleAnswer by Lundin for How can I use a global variable in a STM32WB55 BLE...
"Global variables" (variables with external linkage) should be avoided in C programs.There are a few rare exceptions to this rule, such as when implementing a hardware register map or perhaps when...
View ArticleAnswer by Lundin for More efficient circuit than using a relay?
24VDC is an industry standard for low voltages and relays, so go for that. In this case a relay which works on 24VDC coil voltage. There is plenty of such if you just search for "24VDC timer relay"....
View ArticleAnswer by Lundin for Raspberry Pi Pico, ensuring the circuit diagram is correct
As noted in comments, the regulator absolutely needs to be grounded down. Ideally with the shortest path back to the supply ground as possible.You cannot place arbitrary diodes and passives in the...
View ArticleAnswer by Lundin for Solder is getting 'pasty' when heated
Likely it is bad quality solder. It's very common that poor quality brands tamper with the tin/lead ratio so that it's more like 50/50. Only buy solder from reputable sources. Rosin core no-clean flux...
View ArticleAnswer by Lundin for How to program an STM32 MCU on a custom PCB
Normally you do not program MCUs through on-board circuitry at all; that's an evaluation board thing for rapid testing. Placing such circuits on the board itself will bloat the BoM, making it...
View ArticleAnswer by Lundin for How do I convert a structure's data to the character...
Regarding strings and UART:char is supposedly there because this should be a byte stream and not because they expect you to send it as an ASCII string (which is an inefficient format). In that case...
View ArticleAnswer by Lundin for RS485 to CAN converter
When speaking of any form of data communication, it is important to be aware of the OSI model. Normally in embedded systems, it can be simplified to 3 layers: physical, data link and application.UART...
View ArticleAnswer by Lundin for Dirty VS clean ground: How to tie grounds?
Assuming standard 24V or lower voltage electronics, then the general rule for systems in "dirty" environments with lots of EMI is to connect all grounds together, directly. And eventually to chassis,...
View ArticleComment by Lundin on What can cause these CAN signal distortions?
What's the signal pin-out in the cable like? Are you using the supply ground as reference for CAN? Are there large ground currents from those motors on that same ground? Check out What are the most...
View ArticleComment by Lundin on SMPS Controller Max Output Voltage
All info seems to be in the datasheet. If I'm reading it correctly then the maximum feedback voltage is 5.075 for the 5V part. Why must your ADC have 5V as reference though? We often pick a lower...
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Answer by Lundin for Problem in programming a Freescale MCU (MCR908JK1)
This is an old 68HC08 dating back before standardized single-wire interfaces. That thing came with its own evil, proprietary programming interface from Motorola called "MON08".The 2x5 connector on your...
View ArticleComment by Lundin on What is the right capacitor amount in this circuit...
@TurboJ They managed to type 22uF for C1. So it is not about keyboards or locale, it's just a sloppy schematic. The resistors have temperature rating in Kelvin too, apparently... 1K is pretty darn cold.
View ArticleComment by Lundin on What sort of connector is this (Gtech robotic lawnmower)?
No such adapter will exists unless you solder one yourself. Why not simply cut the wires of which ever connector is inconvenient and replace it with the other one though? These would likely be some...
View ArticleComment by Lundin on STM32 SWD Debug Hangs
SWD simply isn't designed to be used in noisy environments. Step 1 before anything else is to slow down the SWD speed as much as possible.
View ArticleComment by Lundin on Assistance in where to find information for SMD...
The schematic would be proprietary info belong to whoever made the board. And what does "missing a SMD cap" even mean? Did you chisel it away? Did it explode? Was it purposely not mounted by the...
View ArticleComment by Lundin on Switching 12V 50A with Arduino
50Ah is battery life time not maximum current.
View ArticleComment by Lundin on The maximum distance supported between two nodes in an...
How long is a rope? Anyone telling you the range of an RF part like that is at best doing a very rough estimation. At best the might offer a line of sight range, but mesh networks are rarely ever line...
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Answer by Lundin for how safe are regular SMD diodes / common cathode...
There are two aspects here: will the diode break because of ESD and will the diode help against ESD.Regular diodes do not like to get massive voltage spikes handed to them. Some semiconductor expert...
View ArticleComment by Lundin on Can anyone help me to solve this circuit?
Addition and basic physics t=1/f ought to be enough.
View ArticleComment by Lundin on Help debugging a chicken coop door problem
If there's been a short caused by water, then any part could be broken. Including one part of the MCU - it's common that one hardware peripheral inside the MCU dies but that the rest of it keeps...
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