JAJSBS2F January   2012  – April 2017 TPS7A7001

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 改訂履歴
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Enable (EN)
      2. 7.3.2 Internal Current Limit
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Dropout Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input Capacitor (IN)
      2. 8.1.2 Output Capacitor (OUT)
      3. 8.1.3 Feedback Resistors (FB)
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Layout Recommendation to Improve PSRR and Noise Performance
    2. 10.2 Layout Example
    3. 10.3 Thermal Protection
    4. 10.4 Power Dissipation
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 デバイス・サポート
      1. 11.1.1 デバイスの項目表記
    2. 11.2 ドキュメントのサポート
      1. 11.2.1 関連資料
    3. 11.3 ドキュメントの更新通知を受け取る方法
    4. 11.4 コミュニティ・リソース
    5. 11.5 商標
    6. 11.6 静電気放電に関する注意事項
    7. 11.7 Glossary
  12. 12メカニカル、パッケージ、および注文情報

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

8.1 Application Information

8.1.1 Input Capacitor (IN)

Although an input capacitor is not required for stability, it is recommended to connect a 1-µF to 10-µF low equivalent series resistance (ESR) capacitor across IN and GND near the device.

8.1.2 Output Capacitor (OUT)

The TPS7A7001 is stable with standard ceramic capacitors with capacitance values from 4.7 µF to 47 µF without a feedforward capacitor. For output capacitors from 47 µF to 200 µF, a feedforward capacitor of at least 220 pF must be used. The TPS7A7001 is evaluated using an X5R-type, 10-µF ceramic capacitor. X5R- and X7R-type capacitors are recommended because of minimal variation in value and ESR over temperature. Maximum ESR must be less than 1 Ω.

As with any regulator, increasing the size of the output capacitor reduces overshoot and undershoot magnitude, but increases duration of the transient response.

8.1.3 Feedback Resistors (FB)

The voltage on the FB pin sets the output voltage and is determined by the values of R1 and R2. The values of R1 and R2 can be calculated for any voltage using the formula given in Equation 1:

Equation 1.  TPS7A7001 q_vout_bvs134.gif

Table 2 shows the recommended resistor values for the best performance of the TPS7A7001. If the values in Table 2 are not used, keep the value of R2 between 27 kΩ and 33 kΩ. In Table 2, E96 series resistors are used. For the actual design, pay attention to any resistor error factors.

Table 2. Sample Resistor Values for Common Output Voltages

VOUT R1 R2
1.0 V 30.1 kΩ 30.1 kΩ
1.2 V 42.2 kΩ 30.1 kΩ
1.5 V 60.4 kΩ 30.1 kΩ
1.8 V 78.7 kΩ 30.1 kΩ
2.5 V 121 kΩ 30.1 kΩ
3.0 V 150 kΩ 30.1 kΩ
3.3 V 169 kΩ 30.1 kΩ
5.0 V 274 kΩ 30.1 kΩ

8.2 Typical Application

TPS7A7001 pg1_sbvs134.gif Figure 6. Typical Application

8.2.1 Design Requirements

Table 3 lists the design parameters.

Table 3. Design Parameters

PARAMETER DESIGN REQUIREMENT
Input voltage 3.3 V
Output voltage 2.5 V
Maximum output current 1.2 A

8.2.2 Detailed Design Procedure

Select the desired device based on the output voltage.

Provide an input supply with adequate headroom to account for dropout and output current to account for the GND terminal current, and power the load.

8.2.3 Application Curve

TPS7A7001 g002_bvs134.png
VIN = 5.0 V, VOUT = 3.3 V
Figure 7. Power-Supply Ripple Rejection vs Frequency