# Bourns Fixed Resistors

What is a standard resistance value?

Bourns® fixed resistors typically follow the E24/E24+96 series standard resistor values. The first 2 or 3 digits are derived from the standard value table, while the last digit is the multiplier representing the number of zeros to follow. For some resistors, Bourns utilizes a popular resistance values table:

What is the resistance tolerance?
Bourns offers are ±1% and ±5% tolerance. Precision thin film resistors have a very low tolerance down to ±0.01 %. I have linked their chip resistors above but they also have through-hole resistors in both ±1% and ±5% you can find here.

What is the maximum working voltage for a resistor?
The maximum continuous working voltage of the resistor depends on the resistance value and the rated power of the resistor. It can be calculated with formula V=√(PR). The maximum working voltage cannot exceed the limit specified on the product data-sheet.
For example:
The maximum working voltage limit of the Bourns® Model CR0603 Series thick film chip resistor is 75 V and its power rating is 0.1 W based on the product data-sheet.
Maximum working voltage of Model CR0603 with resistance value 1 kΩ is V=√(P
R) = √(0.11000) = 10 V
The maximum working voltage of Model CR0603 with resistance value 100 kΩ would be V=√(P
R) = √(0.1*100000) = 100 V but it is higher than the 75 V maximum working voltage limit specified on the datasheet. Thus, the maximum working voltage of Model CR0603 Series 100 kΩ resistor is 75 V.

Are Bourns® resistors RoHS compliant?
Bourns® fixed resistors conform to the RoHS standard. Some of their resistive networks are available with non-RoHS compliant tin/lead plated terminations, as well. Certificates of Compliance are available for all resistive products on the website. When you are on the Digi-Key website a quick way to tell if any component is RoHS compliant is to check for the leaf below the part number as shown here:

Are Bourns® resistors REACH compliant?
For more details, please refer to the Bourns REACH letter.

If you have a questions that you didn’t see here Bourns may have answered it on their FAQ page.