ZHCSJW0D June   2019  – March 2020

PRODUCTION DATA.

1. 特性
2. 应用
3. 说明
1.     Device Images
4. 修订历史记录
5. Device Comparison Table
6. Pin Configuration and Functions
7. Specifications
8. Detailed Description
1. 8.1 Overview
2. 8.2 Functional Block Diagram
3. 8.3 Feature Description
4. 8.4 Device Functional Modes
9. Application and Implementation
1. 9.1 Application Information
2. 9.2 Typical Application
1. 9.2.1 Design Requirements
2. 9.2.2 Detailed Design Procedure
3. 9.2.3 Application Curves
3. 9.3 System Example
10. 10Power Supply Recommendations
11. 11Layout
12. 12器件和文档支持
1. 12.1 器件支持
2. 12.2 保障资源
3. 12.3 商标
4. 12.4 静电放电警告
5. 12.5 Glossary
13. 13机械、封装和可订购信息

• DGR|8
• DLC|8
• YBG|6
• DLC|8

#### 9.2.2.1 Inductor Selection

The inductor value affects the peak-to-peak ripple current, PWM-to-PFM transition point, output voltage ripple, and efficiency. The selected inductor has to be rated for its DC resistance and saturation current. The inductor ripple current (ΔIL) decreases with higher inductance and increases with higher VIN or VOUT and can be estimated according to Equation 4.

Equation 5 calculates the maximum inductor current under static load conditions. The saturation current of the inductor must be rated higher than the maximum inductor current, as calculated with Equation 5. This is recommended because during a heavy load transient the inductor current rises above the calculated value. A more conservative way is to select the inductor saturation current according to the high-side MOSFET switch current limit, ILIMF.

Equation 4.
Equation 5.

where

• f is the switching frequency
• L is the inductance
• ΔIL is the peak-to-peak inductor ripple current
• ILmax is the maximum inductor current

Table 4 shows a list of possible inductors.

### Table 4. List of Possible Inductors(1)

INDUCTANCE [µH] INDUCTOR TYPE SIZE [L x W x T] SUPPLIER
2.2 DFE201612E [2.0 mm x 1.6 mm x 1.2 mm max.] muRata
2.2 DFE201210S [2.0 mm x 1.2 mm x 1.0 mm max.] muRata