Product Quality Guide

TAIYO YUDEN’s products are classified into three quality grades.

Quality Grade Category
One A: durability type, high-reliability grade lineups for automotive applications
Two B: high-reliability grade lineups for Industrial equipment applications
C: high-reliability grade lineups for automotive applications
M: high-reliability grade lineups for medical device applications
Three S: general equipment grade lineups for consumer electronics applications
L: general equipment grade lineups for medical device applications

Please refer to application guides for target application uses of each market.

Market Requirement Required Quality Quality Grade Three Quality Grade Two Quality Grade One

Automotive Application Guide

We classify automotive electronic equipment into the following four application categories and set usable application categories for each of our products. Therefore, we have the corresponding product series (the part number code of 2nd digit from the left side is “A” or “C”). When using our products for automotive electronic equipment, please be sure to check such application categories and use the corresponding product series accordingly. Should you have any questions on this matter, please contact us.

Industrial Application Guide

We have the product series (the part number code of 2nd digit from the left side is “B”) intended for use in telecommunications infrastructure and industrial equipment (its typical examples are as shown in the table below). Therefore, when using our products for these equipment, please check it carefully by referring to the part number or the individual product specification sheets and use the corresponding product series. Should you have any questions on this matter, please contact us.

Medical Application Guide

According to the medical devices classified as GHTF Classes A to C (Japan Classes I to III), we have the corresponding product series (the part number code of 2nd digit from the left side is “M” or “L”) intended for use in the medical devices. Therefore, when using our products for the medical devices, please be sure to check the classification based on the GHTF Rules and use the corresponding product series.

On the other hand, we donʼt have the product series intended for use in (i) all medical devices classified as GHTF Class D (Japan Class IV) and (ii) implantable medical devices (bone-anchored hearing aid, artificial retina system, and external unit which is connected to internal unit which is implanted in a body, etc.). Therefore, please do not incorporate our products into these medical devices. Should you have any questions on this matter, please contact us.

When demand for passive components increases and supply becomes tight, or when there is an outbreak of an infectious disease such as COVID-19, we have established a system to preferentially ship medical-grade products.

  • ※Note: It is prohibited that our products are used in some medical devices such as implantable medical devices.

Mobile Application Guide

We have the product series (the 2nd code from the left side of the part number is “E”) intended for use only in mobile devices (its typical examples are as shown in the table below), where the applications covered by this product series are limited to mobile devices among general electronic equipment for consumer. The design, specifications and operating environment, etc. differ from those of the product series for “General Electronic Equipment” (Category: S) as described below, so please check the individual product specification sheets for details. The product series for “General Electronic Equipment” (Category: S) can also be used for mobile devices. Should you have any questions on this matter, please contact us.

Design of Product Series Only for Mobile Devices (Category: E)

The products in this product series are designed to have a useful life of 5 years or more if the following 2 conditions are met (Cf. for the product series for “General Electronic Equipment” (Category: S), the useful life is 10 years or more):


(1)The product temperature in the actual equipment ≦ guaranteed product temperature - 30 (°C),and

(2)80% of the rated voltage or less


The useful life under actual operating conditions can be predicted from the following graph.

  • ※The useful life is a reference for predicting the time when the cumulative failure rate reaches 1%, and the data is not intended as a guarantee of the product lifetime. Please use it only as a guide when designing mobile devices.
Quality Grade Difference(968KB)