SMD code 4R0 — 4 Ω
A surface-mount resistor has no bands. This one is a three-digit marking: the R is the decimal point — 4.0 Ω. Parts marked this way are usually ±5% or ±2%.
4R0
reads as
4 Ω
How much it can take
| Across it | Dissipated | Smallest package that copes |
|---|---|---|
| 5 V | 6.25 W | no standard part — needs a power resistor or a heatsink |
| 12 V | 36 W | no standard part — needs a power resistor or a heatsink |
What you can actually get
Parts made
6
at this value
Common packages
TO-220-2 · 2515 · 2817
Codes you will mistake it for
One character apart from 4R0. On a 0402 part these are a fraction of a millimetre of printing — worth a second look before you solder.