SLVSB49F November   2011  – January 2015 TPS22910A , TPS22912C

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, Typical
    7. 8.7  Typical DC Characteristics
    8. 8.8  Typical AC Characteristics, TPS22910A
    9. 8.9  Typical AC Characteristics, TPS22912C
    10. 8.10 Typical AC Characteristics, TPS22913B
    11. 8.11 Typical AC Characteristics, TPS22913C
  9. 9 Parameter 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 Under-Voltage Lockout
      3. 10.3.3 Full-Time Reverse Current Protection
    4. 10.4 Device Functional Modes
  11. 11Application and Implementation
    1. 11.1 Application Information
      1. 11.1.1 VIN to VOUT Voltage Drop
      2. 11.1.2 On/Off Control
      3. 11.1.3 Input Capacitor (Optional)
      4. 11.1.4 Output Capacitor (Optional)
    2. 11.2 Typical Application
      1. 11.2.1 Design Requirements
      2. 11.2.2 Detailed Design Procedure
        1. 11.2.2.1 Inrush Current
      3. 11.2.3 Application Curves
        1. 11.2.3.1 Typical Application Characteristics for TPS22910A
        2. 11.2.3.2 Typical Application Characteristics for TPS22912C
        3. 11.2.3.3 Typical Application Characteristics For TPS22913B
        4. 11.2.3.4 Typical Application Characteristics for TPS22913C
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
    3. 13.3 Thermal Considerations
  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

11.1 Application Information

This section will highlight some of the design considerations when implementing this device in various applications. A PSPICE model for this device is also available in the product page of this device on www.ti.com for further aid.

11.1.1 VIN to VOUT Voltage Drop

The VIN to VOUT voltage drop in the device is determined by the RON of the device and the load current. The RON of the device depends upon the VIN condition of the device. Refer to the RON specification of the device in the Electrical Characteristics table of this datasheet. Once the RON of the device is determined based upon the VIN conditions, use Equation 1 to calculate the VIN to VOUT voltage drop:

Equation 1. ΔV = ILOAD × RON

Where,

ΔV = Voltage drop from VIN to VOUT

ILOAD = Load current

RON = On-resistance of the device for a specific VIN

An appropriate ILOAD must be chosen such that the IMAX specification of the device is not violated.

11.1.2 On/Off Control

The ON pin controls the state of the switch. The ON pin has a low threshold, making it capable of interfacing with low-voltage signals. The ON pin is compatible with standard GPIO logic thresholds. It can be used with any microcontroller with 1.2 V or higher GPIO voltage. This pin cannot be left floating and must be driven either high or low for proper functionality.

11.1.3 Input Capacitor (Optional)

To limit the voltage drop on the input supply caused by transient inrush currents when the switch turns on into a discharged load capacitor or short-circuit, a capacitor needs to be placed between VIN and GND. A 1-µF ceramic capacitor, CIN, placed close to the pins, is usually sufficient. Higher values of CIN can be used to further reduce the voltage drop during high current applications. When switching heavy loads, it is recommended to have an input capacitor about 10 times higher than the output capacitor to avoid excessive voltage drop.

11.1.4 Output Capacitor (Optional)

Due to the integrated body diode in the PMOS switch, a CIN greater than CL is highly recommended. A CL greater than CIN can cause VOUT to exceed VIN when the system supply is removed. This could result in current flow through the body diode from VOUT to VIN. A CIN to CL ratio of 10 to 1 is recommended for minimizing VIN dip caused by inrush currents during startup, however a 10 to 1 ratio for capacitance is not required for proper functionality of the device. A ratio smaller than 10 to 1 (such as 1 to 1) could cause slightly more VIN dip upon turn-on due to inrush currents. This can be mitigated by using a device with a longer rise time.

11.2 Typical Application

simp_sch_slvscl7.gifFigure 50. Typical Application

11.2.1 Design Requirements

Design Parameter Example Value
VIN 1.5 V to 5 V
CL 0.1 µF to 1 µF
Maximum Acceptable Inrush Current 1 A

11.2.2 Detailed Design Procedure

11.2.2.1 Inrush Current

When the switch is enabled, the output capacitors must be charged up from 0-V to VIN voltage. This charge arrives in the form of inrush current. Inrush current can be calculated using the following equation:

Equation 2. inrush_eq_slvsb49.gif

Where,

C = Output capacitance

dvdt_eq_slvsb49.gif = Output slew rate

The TPS22910A, TPS22912C, and TPS22913B/C offer several different rise time options to control the inrush current during turn-on. The appropriate device can be selected based upon the maximum acceptable slew rate which can be calculated using the design requirements and the inrush current equation. An output capacitance of 1.0 µF will be used since the inrush follows the following equations:

Equation 3. dvdt2_eq_slvsb49.gif
Equation 4. dvdt3_eq_slvsb49.gif

To ensure an inrush current of less than 1 A, a device with a slew rate less than 1 V/µs must be used

The TPS22910A has a typical rise time of 1 µs at 3.3 V . This results in a slew rate of 3.3 V/µs which is above the 1 V/µs requirement meaning the TPS22910 could not be used to meet the design requirements.

The TPS22913B has a typical rise time of 66 µs at 3.3 V. This results in a slew rate of 50 mV/µs which is below the 1 V/µs requirement; therefor, the TPS22913B could be used to meet the design requirements. The TPS22912C or TPS22913C have lower slew rates than the TPS22913B, so they could also be used, but the output would rise more slowly.

11.2.3 Application Curves

11.2.3.1 Typical Application Characteristics for TPS22910A

The dark blue curve (Channel 1) represents the VOUT pin of the device. The light blue curve (Channel 2) represents the ON pin of the device.

SC001_lvsb49.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 0.1 µF RL = 10Ω
Figure 51. Turn-on Response
SC003_lvsb49.png
VIN = 5 V TA = 25°C CIN =10 µF
CL = 1 µF RL = 10 Ω
Figure 53. Turn-on Response Time
SC005_lvsb49.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 0.1 µF RL = 10Ω
Figure 55. Turn-on Response Time
SC007_lvsb49.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10Ω
Figure 57. Turn-on Response Time
SC002_lvsb49.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 0.1 µF RL = 10Ω
Figure 52. Turn-off Response
SC004_lvsb49.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10Ω
Figure 54. Turn-off Response Time
SC006_lvsb49.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 0.1 µF RL = 10Ω
Figure 56. Turn-off Response Time
SC008_lvsb49.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10Ω
Figure 58. Turn-off Response Time

11.2.3.2 Typical Application Characteristics for TPS22912C

The dark blue curve (Channel 1) represents the VOUT pin of the device. The light blue curve (Channel 2) represents the ON pin of the device.

SC001_lvsb78.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10Ω
Figure 59. Turn-on Response
SC003_lvsb78.png
VIN = 5 V TA = 25°C CIN =10 µF
CL = 1 µF RL = 10 Ω
Figure 61. Turn-on Response Time
SC005_lvsb78.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 63. Turn-on Response Time
SC007_lvsb78.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 65. Turn-on Response Time
SC002_lvsb78.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 60. Turn-off Response
SC004_lvsb78.png
VIN = 5 TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 62. Turn-off Response Time
SC006_lvsb78.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 64. Turn-off Response Time
SC008_lvsb78.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 66. Turn-off Response Time

11.2.3.3 Typical Application Characteristics For TPS22913B

The dark blue curve (Channel 1) represents the VOUT pin of the device. The light blue curve (Channel 2) represents the ON pin of the device.

sc1_lvsb20.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 67. Turn-on Response
sc3_lvsb20.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 69. Turn-on Response Time
sc5_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 71. Turn-on Response Time
sc7_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 73. Turn-on Response Time
sc2_lvsb20.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 68. Turn-off Response
sc4_lvsb20.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 70. Turn-off Response Time
sc6_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 72. Turn-off Response Time
sc8_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 74. Turn-off Response Time

11.2.3.4 Typical Application Characteristics for TPS22913C

The dark blue curve (Channel 1) represents the VOUT pin of the device. The light blue curve (Channel 2) represents the ON pin of the device.

C001_lvsb20.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 75. Turn-On Response Time
C003_lvsb20.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 77. Turn-On Response Time
C005_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 79. Turn-Off Response Time
C007_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 81. Turn-Off Response Time
C002_lvsb20.png
VIN = 5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 76. Turn-Off Response Time
C004_lvsb20.png
VIN = 5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 78. Turn-Off Response Time
C006_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 10 µF
CL = 1 µF RL = 10 Ω
Figure 80. Turn-Off Response Time
C008_lvsb20.png
VIN = 1.5 V TA = 25°C CIN = 1 µF
CL = 0.1 µF RL = 10 Ω
Figure 82. Turn-Off Response Time