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Feb 20, 2024

"Refining Passive Component Selection: A Guide to E-Series Value Selection"

E24 E48 E96 E24 E48 E96 E24 E48 E96 E24 E48 E96 E1 E3 E6 E12
100 100 100 180 178 178 330 316 316 560 562 562 100 100 100 100
102 182 324 576 120
105 105 187 187 332 332 590 590 150 150
107 191 340 604 180
110 110 110 200 196 196 360 348 348 620 619 619 220 220 220
113 200 357 634 270
115 115 205 205 365 365 649 649 330 330
118 210 374 665 390
120 121 121 220 215 215 390 383 383 680 681 681 470 470 470
124 221 392 698 560
127 127 226 226 402 402 715 715 680 680
130 232 412 732 820
130 133 133 240 237 237 430 422 422 750 750 750
137 243 432 768
140 140 249 249 442 442 787 787
143 255 453 806
150 147 147 270 261 261 470 464 464 820 825 825
150 267 475 845
154 154 274 274 487 487 866 866
158 280 499 887
160 162 162 300 287 287 510 511 511 910 909 909
165 294 523 931
169 169 301 301 536 536 953 953
174 309 549 976


The selection of passive component values, such as those for resistors and capacitors, is typically guided by E-series values that align with their precision level. This process involves a few structured steps for value refinement and selection based on the component's precision requirements. Here's a streamlined overview of this process:

1. Determine the Required Precision:
   - Capacitors often utilize E12 series values.
   - Resistors with 10% and 5% tolerance generally adhere to E24 series values.
   - For 1% tolerance resistors, E96 series values are used.
   - Series other than these are rarely employed in standard applications.

2. Value Selection Process:
   To choose a specific value, follow these steps:
   a. Start with the calculated target value.
   b. Round this target value:
      - To 2 significant figures for series E24 and below.
      - To 3 significant figures for series E48 and above.
   c. Locate the closest matching value in the respective E-series table, which will replace the rounded figures.
   
   Example:
   For a target resistance of 16,834.2Ω:
   - First, round to 16,800Ω (for an E24 or lower series, though this example extends into higher precision practice).
   - The closest E96 series value to 168 (significant figures of 16,800) is 169.
   - Therefore, the chosen value is 16.9kΩ for an E96 precision resistor.

   Special Note:
   The value 0 is an exception and does not exist in any of the E-series values.

This structured approach ensures the selection of component values aligns with available standard values and the required precision for the application, optimizing both performance and availability.