SLVSDT2 November   2016 TPS562219A , TPS563219A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  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 Timing Requirements
    7. 6.7 Typical Characteristics
      1. 6.7.1 TPS562219A Characteristics
      2. 6.7.2 TPS563219A Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 The Adaptive On-Time Control and PWM Operation
      2. 7.3.2 Soft Start and Pre-Biased Soft Start
      3. 7.3.3 Power Good
      4. 7.3.4 Current Protection
      5. 7.3.5 Over Voltage Protection
      6. 7.3.6 UVLO Protection
      7. 7.3.7 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Forced CCM Operation
      3. 7.4.3 Standby Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Typical Application, TPS562219A
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Output Voltage Resistors Selection
          2. 8.2.1.2.2 Output Filter Selection
          3. 8.2.1.2.3 Input Capacitor Selection
          4. 8.2.1.2.4 Bootstrap capacitor Selection
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Typical Application, TPS563219A
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedures
          1. 8.2.2.2.1 Output Filter Selection
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
    2. 11.2 Documentation Support
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Community Resources
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

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

The TPS562219A and TPS563219A are typically used as step down converters, which convert a voltage from 4.5 V - 17 V to a lower voltage. Webench software is available to aid in the design and analysis of circuits.

8.2 Typical Application

8.2.1 Typical Application, TPS562219A

TPS562219A TPS563219A Typ_app_2210a_slvsdt2.gif Figure 17. TPS562219A 1.05V/2A Reference Design

8.2.1.1 Design Requirements

For this design example, use the parameters shown in Table 1.

Table 1. Design Parameters

PARAMETER VALUES
Input voltage range 4.5 V to 17 V
Output voltage 1.05 V
Output current 2 A
Output voltage ripple 20 mVpp

8.2.1.2 Detailed Design Procedure

8.2.1.2.1 Output Voltage Resistors Selection

The output voltage is set with a resistor divider from the output node to the VFB pin. It is recommended to use 1% tolerance or better divider resistors. Start by using Equation 2 to calculate VOUT.

To improve efficiency at light loads consider using larger value resistors, too high of resistance are more susceptible to noise and voltage errors from the VFB input current are more noticeable.

Equation 2. TPS562219A TPS563219A Eq02_VOUT_slvscm5.gif

8.2.1.2.2 Output Filter Selection

The LC filter used as the output filter has double pole at:

Equation 3. TPS562219A TPS563219A Eq03_FP_slvscm5.gif

At low frequencies, the overall loop gain is set by the output set-point resistor divider network and the internal gain of the device. The low frequency phase is 180 degrees. At the output filter pole frequency, the gain rolls off at a –40 dB per decade rate and the phase drops rapidly. D-CAP2™ introduces a high frequency zero that reduces the gain roll off to –20 dB per decade and increases the phase to 90 degrees one decade above the zero frequency. The inductor and capacitor for the output filter must be selected so that the double pole of Equation 3 is located below the high frequency zero but close enough that the phase boost provided be the high frequency zero provides adequate phase margin for a stable circuit. To meet this requirement use the values recommended in Table 2.

Table 2. TPS562219A Recommended Component Values

Output Voltage (V) R2 (kΩ) R3 (kΩ) L1(uH) C6 + C7 + C8(µF)
MIN TYP MAX
1 3.09 10.0 1.5 2.2 4.7 20 - 68
1.05 3.74 10.0 1.5 2.2 4.7 20 - 68
1.2 5.76 10.0 1.5 2.2 4.7 20 - 68
1.5 9.53 10.0 1.5 2.2 4.7 20 - 68
1.8 13.7 10.0 1.5 2.2 4.7 20 - 68
2.5 22.6 10.0 2.2 3.3 4.7 20 - 68
3.3 33.2 10.0 2.2 3.3 4.7 20 - 68
5 54.9 10.0 3.3 4.7 4.7 20 - 68
6.5 75 10.0 3.3 4.7 4.7 20 - 68

The inductor peak-to-peak ripple current, peak current and RMS current are calculated using Equation 4, Equation 5 and Equation 6. The inductor saturation current rating must be greater than the calculated peak current and the RMS or heating current rating must be greater than the calculated RMS current.

Use 650 kHz for fSW. Make sure the chosen inductor is rated for the peak current of Equation 5 and the RMS current of Equation 6.

Equation 4. TPS562219A TPS563219A Eq04_Ilpp_slvscm5.gif
Equation 5. TPS562219A TPS563219A Eq05_Ipeak_slvscm5.gif
Equation 6. TPS562219A TPS563219A Eq06_ILO_slvscm5.gif

For this design example, the calculated peak current is 2.34 A and the calculated RMS current is 2.01 A. The inductor used is a TDK CLF7045T-2R2N with a peak current rating of 5.5 A and an RMS current rating of 4.3 A.

The capacitor value and ESR determines the amount of output voltage ripple. The TPS562219A and TPS563219A are intended for use with ceramic or other low ESR capacitors. Recommended values range from 20 µF to 68 µF. Use Equation 7 to determine the required RMS current rating for the output capacitor.

Equation 7. TPS562219A TPS563219A Eq07_ICO_slvscm5.gif

For this design two TDK C3216X5R0J226M 22µF output capacitors are used. The typical ESR is 2 mΩ each. The calculated RMS current is 0.286A and each output capacitor is rated for 4A.

8.2.1.2.3 Input Capacitor Selection

The TPS562219A and TPS563219A require an input decoupling capacitor and a bulk capacitor is needed depending on the application. A ceramic capacitor over 10 µF is recommended for the decoupling capacitor. An additional 0.1 µF capacitor (C3) from pin 3 to ground is optional to provide additional high frequency filtering. The capacitor voltage rating needs to be greater than the maximum input voltage.

8.2.1.2.4 Bootstrap capacitor Selection

A 0.1µF ceramic capacitor must be connected between the VBST to SW pin for proper operation. It is recommended to use a ceramic capacitor.

8.2.1.3 Application Curves

The following application curves were generated using the application circuit of Figure 17.

TPS562219A TPS563219A D006_SLVSCM7.gif Figure 18. TPS562219A Efficiency
TPS562219A TPS563219A D008_SLVSCM7.gif Figure 20. TPS562219A Load Regulation, VI = 5 V
TPS562219A TPS563219A D010_SLVSCM7.gif Figure 22. TPS562219A Line Regulation
TPS562219A TPS563219A Vout_ripple_a_2219_slvsCM7.gif
Figure 24. TPS562219A Output Voltage Ripple
TPS562219A TPS563219A fig26_slvsdt2.gif
Figure 26. TPS562219A Start Up Relative To VI
TPS562219A TPS563219A fig28_slvsdt2.gif
Figure 28. TPS562219A Shut Down Relative To VI
TPS562219A TPS563219A D007_SLVSCM7.gif Figure 19. TPS562219A Light Load Efficiency
TPS562219A TPS563219A D009_SLVSCM7.gif Figure 21. TPS562219A Load Regulation, VI = 12 V
TPS562219A TPS563219A Vin_ripple_2219_slvsCM7.gif Figure 23. TPS562219A Input Voltage Ripple
TPS562219A TPS563219A transient1_2219_slvsCM7.gif
Figure 25. TPS562219A Transient Response
TPS562219A TPS563219A fig27_slvsdt2.gif
Figure 27. TPS562219A Start Up Relative To EN
TPS562219A TPS563219A fig29_slvsdt2.gif
Figure 29. TPS562219A Shut Down Relative To EN

8.2.2 Typical Application, TPS563219A

TPS562219A TPS563219A Typ_app_3219a_slvsdt2.gif Figure 30. TPS563219A 1.05V/3A Reference Design

8.2.2.1 Design Requirements

For this design example, use the parameters shown in Table 3.

Table 3. Design Parameters

PARAMETER VALUE
Input voltage range 4.5 V to 17V
Output voltage 1.05V
Output current 3A
Output voltage ripple 20mVpp

8.2.2.2 Detailed Design Procedures

The detailed design procedure for TPS563219A is the same as for TPS562200 except for inductor selection.

8.2.2.2.1 Output Filter Selection

Table 4. TPS563219A Recommended Component Values

Output Voltage (V) R2 (kΩ) R3 (kΩ) L1 (µH) C6 + C7 + C8 (µF)
MIN TYP MAX
1 3.09 10.0 1.0 1.5 4.7 20 - 68
1.05 3.74 10.0 1.0 1.5 4.7 20 - 68
1.2 5.76 10.0 1.0 1.5 4.7 20 - 68
1.5 9.53 10.0 1.0 1.5 4.7 20 - 68
1.8 13.7 10.0 1.5 2.2 4.7 20 - 68
2.5 22.6 10.0 1.5 2.2 4.7 20 - 68
3.3 33.2 10.0 1.5 2.2 4.7 20 - 68
5 54.9 10.0 2.2 3.3 4.7 20 - 68
6.5 75 10.0 2.2 3.3 4.7 20 - 68

The inductor peak-to-peak ripple current, peak current and RMS current are calculated using Equation 8, Equation 9 and Equation 10. The inductor saturation current rating must be greater than the calculated peak current and the RMS or heating current rating must be greater than the calculated RMS current. Use 650 kHz for ƒSW.

Use 650 kHz for ƒSW. Make sure the chosen inductor is rated for the peak current of Equation 9 and the RMS current of Equation 10.

Equation 8. TPS562219A TPS563219A eq4_IIpp_slvscb0.gif
Equation 9. TPS562219A TPS563219A eq5_IIpeak_slvscb0.gif
Equation 10. TPS562219A TPS563219A eq6_ILO_slvscb0.gif

For this design example, the calculated peak current is 3.505 A and the calculated RMS current is 3.014 A. The inductor used is a TDK CLF7045T-1R5N with a peak current rating of 7.3-A and an RMS current rating of 4.9-A.

The capacitor value and ESR determines the amount of output voltage ripple. The TPS563209 is intended for use with ceramic or other low ESR capacitors. Recommended values range from 20 μF to 68 μF. Use Equation 6 to determine the required RMS current rating for the output capacitor. For this design, three TDK C3216X5R0J226M 22 μF output capacitors are used. The typical ESR is 2 mΩ each. The calculated RMS current is 0.292 A and each output capacitor is rated for 4 A.

8.2.2.3 Application Curves

The following application curves were generated using the application circuit of Figure 30.

TPS562219A TPS563219A D001_SLVSCM7.gif Figure 31. TPS563219A Efficiency
TPS562219A TPS563219A D003_SLVSCM7.gif Figure 33. TPS563219A Load Regulation, VI = 5 V
TPS562219A TPS563219A D002_SLVSCM7.gif Figure 32. TPS563219A Light Load Efficiency
TPS562219A TPS563219A D004_SLVSCM7.gif Figure 34. TPS563219A Load Regulation, VI = 12 V
TPS562219A TPS563219A D005_SLVSCM7.gif Figure 35. TPS563219A Line Regulation
TPS562219A TPS563219A Vout_ripple_a_3219_slvsCM7.gif Figure 37. TPS563219A Output Voltage Ripple
TPS562219A TPS563219A fig39_slvsdt2.gif Figure 39. TPS563219A Start Up Relative To VI
TPS562219A TPS563219A fig41_slvsdt2.gif Figure 41. TPS563219A Shut Down Relative To VI
TPS562219A TPS563219A Vin_ripple_3219_slvsCM7.gif Figure 36. TPS563219A Input Voltage Ripple
TPS562219A TPS563219A transient1_3219_slvsCM7.gif Figure 38. TPS563219A Transient Response
TPS562219A TPS563219A fig40_slvsdt2.gif Figure 40. TPS563219A Start Up Relative To EN
TPS562219A TPS563219A fig42_slvsdt2.gif Figure 42. TPS563219A Shut Down Relative To EN