SLVSBS6A June   2013  – January 2015 TPS22963C , TPS22964C

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Switching Characteristics
    7. 8.7 Typical Electrical Characteristics
    8. 8.8 Typical Switching Characteristics
    9. 8.9 Typical AC Scope Captures at TA = 25ºC
  9. 9 Parametric Measurement Information
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1 On/Off Control
      2. 10.3.2 Quick Output Discharge
    4. 10.4 Device Functional Modes
  11. 11Application and Implementation
    1. 11.1 Application Information
      1. 11.1.1 Input Capacitor
      2. 11.1.2 Output Capacitor
      3. 11.1.3 Standby Power Reduction
      4. 11.1.4 Reverse Current Protection
      5. 11.1.5 Power Supply Sequencing Without a GPIO Input
    2. 11.2 Typical Application
      1. 11.2.1 Design Requirements
      2. 11.2.2 Detailed Design Procedure
        1. 11.2.2.1 Managing Inrush Current
      3. 11.2.3 Application Curves
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Related Links
    2. 14.2 Trademarks
    3. 14.3 Electrostatic Discharge Caution
    4. 14.4 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

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

11 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.

11.1 Application Information

11.1.1 Input Capacitor

It is recommended to place a capacitor (CIN) between VIN and GND pins of TPS22963/64. This capacitor helps to limit the voltage drop on the input voltage supply when the switch turns ON into a discharged load capacitor. A 1-µF ceramic capacitor that is placed close to the IC pins is usually sufficient. Higher values of CIN can be used to further reduce the voltage drop in high current applications.

11.1.2 Output Capacitor

It is recommended to place a capacitor (COUT) between VOUT and GND pins of TPS22963/64. This capacitor acts as a low pass filter along with the switch ON-resistance to remove any voltage glitches coming from the input voltage source. It is generally recommended to have CIN greater than COUT so that once the switch is turned ON, COUT can charge up to VIN without VIN dropping significantly. A 0.1-µF ceramic capacitor that is placed close to the IC pins is usually sufficient.

11.1.3 Standby Power Reduction

app2_lvsbs6.gifFigure 38. Standby Power Reduction

Any end equipment that is being powered from the battery has a need to reduce current consumption in order to keep the battery charged for a longer time. TPS22963/64 helps to accomplish this by turning off the supply to the modules that are in standby state and hence significantly reduces the leakage current overhead of the standby modules.

11.1.4 Reverse Current Protection

The reverse current protection feature prevents the current to flow from VOUT to VIN when TPS22963/64 is disabled. This feature is particularly useful when the output of TPS22963/64 needs to be driven by another voltage source after TPS22963/64 is disabled (for example in a power multiplexer application). In order for this feature to work, TPS22963/64 has to be disabled and either of the following conditions shall be met: VIN > 1 V or VOUT > 1 V.

Figure 39 demonstrates the ideal behavior of reverse current protection circuit in TPS22963/64. After the device is disabled via the ON pin and VOUT is forced to an external voltage VFORCE, a very small amount of current given by IRC,VIN will flow from VOUT to VIN. This will prevent any extra current loading on the voltage source supplying the VFORCE voltage.

app1_lvsbs6.gif
IVIN = Current through VIN pin.
VSRC = Input voltage applied to the device.
VFORCE = External voltage source forced at VOUT pin of the device.
IOUT = Output load current.
Figure 39. Reverse Current Protection

11.1.5 Power Supply Sequencing Without a GPIO Input

app3_lvsbs6.gifFigure 40. Power Supply Sequencing Without a GPIO Input

In many end equipments, there is a need to power up various modules in a pre-determined manner. TPS22963/64 can solve the problem of power sequencing without adding any complexity to the overall system. Figure 40 shows the configuration required for powering up two modules in a fixed sequence. The output of the first load switch is tied to the enable of the second load switch, so when Module 1 is powered the second load switch is enabled and Module 2 is powered.

11.2 Typical Application

TPS22963/64 is an ultra-low ON-resistance, 3-A integrated load switch that is capable of interfacing directly with 1S battery in portable consumer devices such as smartphones, tablets etc. Its wide input voltage range (1 V to 5.5 V) makes it suitable to be used for lower voltage rails as well inside different end equipments to accomplish power sequencing, inrush current control and reducing leakage current in sub-systems that are in standby mode. Figure 41 shows the typical application circuit of TPS22963/64.

typ_app_lvsbs6.gifFigure 41. Typical Application Circuit

11.2.1 Design Requirements

DESIGN PARAMETER EXAMPLE VALUE
VIN 3.3 V
CL 4.7 µF
Maximum Acceptable Inrush Current 30 mA

11.2.2 Detailed Design Procedure

11.2.2.1 Managing Inrush Current

When the switch is enabled, the output capacitors must be charged up from 0 V to the set value (3.3 V in this example). This charge arrives in the form of inrush current. Inrush current can be calculated using the following equation:

Equation 1. Q3_Iinhush_slvsco0.gif

where

  • C = output capacitance
  • dV = output voltage
  • dt = rise time

The TPS22963/64 offers a controlled rise time for minimizing inrush current. This device can be selected based upon the minimum acceptable rise time which can be calculated using the design requirements and the inrush current equation. An output capacitance of 4.7 µF will be used since the amound of inrush current increases with output capacitance:

Equation 2. 30 mA = 4.7 µF x 3.3 V / dt
Equation 3. dt = 517 µs

To ensure an inrush current of less than 30 mA, a device with a rise time greater than 517 µs must be used. The TPS22963/64 has a typical rise time of 715 µs at 3.3 V which meets the above design requirements.

11.2.3 Application Curves

app_curve_slvsbs6.gifFigure 42. TPS22963/64 Inrush Current with 4.7 µF Output Capacitor