ZHCSJG8I July 2010 – October 2019 TPS63020 , TPS63021
PRODUCTION DATA.
- 1 特性
- 2 應(yīng)用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
- 6 Specifications
- 7 Detailed Description
- 8 Application and Implementation
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機械、封裝和可訂購信息
封裝選項
機械數(shù)據(jù) (封裝 | 引腳)
- DSJ|14
散熱焊盤機械數(shù)據(jù) (封裝 | 引腳)
- DSJ|14
訂購信息
8.2.2.2 Inductor Selection
The inductor selection is affected by several parameters such as the following:
- Inductor ripple current
- Output voltage ripple
- Transition point into Power Save Mode
- Efficiency
See Table 2 for a list of typical inductors.
For high efficiencies, the inductor must have a low DC resistance to minimize conduction losses. Especially at high-switching frequencies, the core material has a high impact on efficiency. When using small chip inductors, the efficiency is reduced mainly due to higher inductor core losses. This needs to be considered when selecting the appropriate inductor. The inductor value determines the inductor ripple current. The larger the inductor value, the smaller the inductor ripple current and the lower the conduction losses of the converter. Conversely, larger inductor values cause a slower load transient response. Use Equation 2 to avoid saturation of the inductor when calculating the peak current for the inductor in steady state operation. Only the equation which defines the switch current in boost mode is shown because this provides the highest value of current and represents the critical current value for selecting the right inductor.
where
- D = duty cycle in boost mode
- f = converter switching frequency (typical 2.5 MHz)
- L = inductor value
- η = estimated converter efficiency (use the number from the efficiency curves or 0.9 as an assumption)
NOTE
The calculation must be done for the minimum input voltage in boost mode.
Calculating the maximum inductor current using the actual operating conditions gives the minimum saturation current of the inductor needed. It is recommended to choose an inductor with a saturation current 20% higher than the value calculated using Equation 2. Table 2 lists the possible inductors.
Table 2. List of Recommended Inductors (1)
| INDUCTOR VALUE [µH] | SATURATION CURRENT [A] | DCR [mΩ] | PART NUMBER | MANUFACTURER | SIZE (LxWxH mm) |
|---|---|---|---|---|---|
| 1.5 | 5.1 | 15 | XFL4020-152ME | Coilcraft | 4 x 4 x 2.1 |
| 1.5 | 5.4 | 24 | FDV0530S-H-1R5M | muRata | 5 x 5 x 3 |