🔌 Elektroniikka
Vastuksen dekoodarit, LED-laskurit, kondensaattorityökalut ja muuta elektroniikkaharrastajille
Dekoodaa 4- ja 5-nauhan vastuksen värikoodit välittömästi. Ilmainen visuaalinen laskuri.
Avaa työkalu →Laske LED-piirin vastus. Syötä jännite ja virta.
Avaa työkalu →Dekoodaa 3-numeroiset keraamiset kondensaattorikoodit (esim. 104 = 100nF).
Avaa työkalu →Laske jännitteenjakajan lähtöjännite. Syötä Vin, R1, R2.
Avaa työkalu →Laske taajuus, pulssisuhde ja ajoitus 555-ajastinpiireille.
Avaa työkalu →Laske PCB-kuparijohtimen vähimmäisleveys annetulle virralle IPC-2221 standardin mukaan.
Avaa työkalu →AWG-johdinpaksuustaulukko halkaisijalla, pinta-alalla, resistanssilla ja maksimivirralla.
Avaa työkalu →Laske aikavakio, latausaika ja purkautumiskäyrät RC-piireille.
Avaa työkalu →Dekoodaa 4-nauhan kelan värikoodit induktanssiksi µH ja mH.
Avaa työkalu →Lisää laitteita, näe kokonaiswattiteho, päivittäiset kWh ja vuosittaiset sähkökustannukset
Avaa työkalu →Dekoodaa 3-, 4-numeroiset ja EIA-96 SMD-vastuskoodit.
Avaa työkalu →Component maths for people with a breadboard in front of them. These tools cover the calculations you hit repeatedly while building a circuit: what resistor a part needs, what a colour band or SMD marking means, how wide a trace has to be, and how long an RC network takes to settle.
Everything is worked in the open. Each tool shows the formula it used and the numbers it put into it, so you can check the result against your own working rather than trusting a black box — which matters when the consequence of a wrong answer is a dead component.
Which tool do I want?
| If you… | Use |
|---|---|
| You have a resistor in hand and need its value | Vastuksen värikoodidekooderi |
| The part is surface-mount with a 3 or 4 character code | SMD-vastuskoodidekooderi |
| You are driving an LED and need the series resistor | LED-vastuslaskuri |
| You need to drop a voltage down to a reference level | Jännitteenjakajalaskuri |
| You are sizing wire for a current, or worried about heat | Johdinpaksuus (AWG) -viite |
| You are laying out a board and need copper width | PCB-johtimen leveyslaskuri |
| You are building a timer or oscillator | 555-ajastinlaskuri |
| You need a time constant for filtering or debouncing | RC-aikavakiolaskuri |
Tolerance is the thing beginners forget
Every calculation here produces an exact number, and no component you can buy is exact. A resistor sold as 220 Ω with a gold band is guaranteed only to sit within 5% of that — anywhere from 209 to 231 Ω. Stack a few 5% parts in one divider and the output can drift further than the reading you were trying to achieve.
This matters most where a result feeds a threshold. A divider setting a comparator trip point, a timing network deciding a pulse width, a current limit sitting just under a part's maximum — in those places, work out what the answer becomes at the tolerance extremes, not just at the nominal value. Where it matters, buy 1% parts; they cost almost nothing more.
The same applies to the standard value the tools round to. E24 gives you 24 values per decade, so the nearest stocked resistor to a calculated 237 Ω is 240 Ω. That is usually fine, and the tools tell you both numbers so you can decide.