476 capacitor value
47 µF
47,000,000 pF · 47000 nF · 47 µF
| Marked code | 476 |
| Picofarads | 47,000,000 pF |
| Nanofarads | 47000 nF |
| Microfarads | 47 µF |
| Farads | 4.70e-5 F |
Reading the code
The three digits are not a part number. The first two are the value in picofarads and the third says what to do with them:
47 × 106 = 47,000,000 pF
So 476 is 47 followed by 6 zeros: 47,000,000 pF. The code is always in picofarads even when the part is sold in microfarads, which is the whole difficulty with it — a capacitor marked 476 is stocked as 47 µF and the two numbers look nothing alike.
What 47 µF does at frequency
A capacitor's opposition to a signal is its reactance, 1 ÷ (2πfC), and it falls as the frequency rises. Over the range of frequencies a circuit can put across it, a 47 µF part covers several orders of magnitude:
| Frequency | Reactance |
|---|---|
| 50 Hz — mains | 67.73 Ω |
| 1 kHz — audio | 3.39 Ω |
| 100 kHz — switching | 33.9 mΩ |
| 10 MHz — RF | 0.3 mΩ |
Ten times the frequency is a tenth of the reactance, every time — which is why choosing a decoupling capacitor is really choosing the frequency band you want it to be low-impedance across, and why boards carry several sizes in parallel rather than one large one.
The letter after the number
A code like 476K carries a tolerance letter. It is not part of the value:
| Letter | Tolerance | 47 µF means |
|---|---|---|
476J | ±5% | 44.65 µF to 49.35 µF |
476K | ±10% | 42.3 µF to 51.7 µF |
476M | ±20% | 37.6 µF to 56.4 µF |
476Z | +80% / −20% | 37.6 µF to 84.6 µF |
A Z is worth knowing about. +80%/−20% is a real tolerance on cheap high-permittivity ceramics, and it means a part marked 476Z can legitimately be anything from 37.6 µF to 84.6 µF. Those go in decoupling positions where only the rough size matters, never in a timing or filter position.
Where 47 µF turns up
Microfarads and up is bulk energy storage: holding a rail up between switching cycles, smoothing a supply, or coupling a signal that goes down to a few hertz. Above about 10 µF ceramics give way to electrolytics and tantalums, which is why the code runs out here.
Frequently asked questions
What is the value of a 476 capacitor?
47 µF — 47,000,000 pF · 47000 nF · 47 µF. The first two digits are the value in picofarads and the third is how many zeros follow, so 476 is 47 followed by 6 zeros = 47,000,000 pF.
What is a 476 capacitor in µF?
47 µF. Going from picofarads to microfarads is six decimal places, which is where most of the confusion with these codes comes from — 47,000,000 pF, 47000 nF and 47 µF are the same capacitor written three ways.
What does the letter after 476 mean?
Tolerance. 476K is ±10%, 476J is ±5% and 476M is ±20% — so a 476K is anywhere from 42.3 µF to 51.7 µF and still in specification. A Z means +80%/−20%, which is not a mistake: some ceramic dielectrics really are that loose.
What is the impedance of a 476 capacitor at 1 kHz?
3.39 Ω. Reactance is 1 ÷ (2πfC), so it falls as the frequency rises: the same part is 33.9 mΩ at 100 kHz and 0.3 mΩ at 10 MHz.
Nearby codes
- 566 capacitor — 56 µF
- 686 capacitor — 68 µF
- 826 capacitor — 82 µF
- 108 capacitor — 0.1 pF
- 128 capacitor — 0.12 pF
- 158 capacitor — 0.15 pF
- 188 capacitor — 0.18 pF
- 228 capacitor — 0.22 pF
- 278 capacitor — 0.27 pF
- 338 capacitor — 0.33 pF