JAJSOK1 October   2024 TPS62810-EP , TPS62811-EP , TPS62812-EP , TPS62813-EP

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Parameter Measurement Information
    1. 7.1 Schematic
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Precise Enable
      2. 8.3.2 COMP/FSET
      3. 8.3.3 MODE/SYNC
      4. 8.3.4 Spread Spectrum Clocking (SSC)
      5. 8.3.5 Undervoltage Lockout (UVLO)
      6. 8.3.6 Power-Good Output (PG)
      7. 8.3.7 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Pulse Width Modulation (PWM) Operation
      2. 8.4.2 Power Save Mode Operation (PWM/PFM)
      3. 8.4.3 100% Duty-Cycle Operation
      4. 8.4.4 Current Limit and Short-Circuit Protection
      5. 8.4.5 Foldback Current Limit and Short-Circuit Protection
      6. 8.4.6 Output Discharge
      7. 8.4.7 Soft Start/Tracking (SS/TR)
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Programming the Output Voltage
      2. 9.1.2 Inductor Selection
      3. 9.1.3 Capacitor Selection
        1. 9.1.3.1 Input Capacitor
        2. 9.1.3.2 Output Capacitor
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 Voltage Tracking
      2. 9.3.2 Synchronizing to an External Clock
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 サード・パーティ製品に関する免責事項
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 ドキュメントの更新通知を受け取る方法
    4. 10.4 サポート・リソース
    5. 10.5 Trademarks
    6. 10.6 静電気放電に関する注意事項
    7. 10.7 用語集
  12. 11Revision History
  13. 12Mechanical, 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

8.3.2 COMP/FSET

This pin lets the user set two different parameters independently:

  • Internal compensation settings for the control loop
  • The switching frequency in PWM mode from 1.8MHz to 4MHz

A resistor from COMP/FSET to GND changes the compensation and switching frequency. The change in compensation allows the user to adapt the device to different values of output capacitance. The resistor must be placed close to the pin to keep the parasitic capacitance on the pin to a minimum. The compensation setting is sampled when the converter starts up, so a change in the resistor during operation only has an effect on the switching frequency, but not on the compensation.

To save external components, the pin can also be directly tied to VIN or GND to set a pre-defined switching frequency or compensation. Do not leave the pin floating.

The switching frequency has to be selected based on the input voltage and the output voltage to meet the specifications for the minimum on time and minimum off time.

For example: VIN = 5V, VOUT = 1V --> duty cycle (DC) = 1V / 5V = 0.2

  • with ton = DC × T --> ton,min = 1 / fs,max × DC
  • --> fs,max = 1 / ton,min × DC = 1 / 0.075µs × 0.2 = 2.67MHz

The compensation range has to be chosen based on the minimum capacitance used. The capacitance can be increased from the minimum value as given in Table 8-1 and Table 8-2, up to a maximum of 470µF in all of the three compensation ranges. If the capacitance of an output changes during operation, for example, when load switches are used to connect or disconnect parts of the circuitry, the compensation must be chosen for the minimum capacitance on the output. With large output capacitance, the compensation must be done based on that large capacitance to get the best load transient response. Compensating for large output capacitance, but placing less capacitance on the output, can lead to instability.

The switching frequency for the different compensation settings is determined by the following equations.

For compensation (comp) setting 1:

Equation 1. TPS62810-EP TPS62811-EP TPS62812-EP TPS62813-EP

For compensation (comp) setting 2:

Equation 2. TPS62810-EP TPS62811-EP TPS62812-EP TPS62813-EP

For compensation (comp) setting 3:

Equation 3. TPS62810-EP TPS62811-EP TPS62812-EP TPS62813-EP
Table 8-1 Switching Frequency and Compensation for TPS62810-EP (4A) and TPS62813-EP (3A)
COMPENSATIONRCFSWITCHING FREQUENCYMINIMUM OUTPUT
CAPACITANCE
FOR VOUT < 1V		MINIMUM OUTPUT
CAPACITANCE
FOR 1V ≤ VOUT < 3.3V		MINIMUM OUTPUT
CAPACITANCE
FOR VOUT ≥ 3.3V
For the smallest output capacitance
(comp setting 1)		10kΩ ... 4.5kΩ1.8MHz (10kΩ) ... 4MHz (4.5kΩ)
according to Equation 1		53µF32µF27µF
For medium output capacitance
(comp setting 2)		33kΩ ... 15kΩ1.8MHz (33kΩ) ... 4MHz (15kΩ)
according to Equation 2		100µF60µF50µF
For large output capacitance
(comp setting 3)		100kΩ ... 45kΩ1.8MHz (100kΩ) ... 4MHz (45kΩ)
according to Equation 3		200µF120µF100µF
For the smallest output capacitance
(comp setting 1)		tied to GNDInternally fixed 2.25MHz53µF32µF27µF
For large output capacitance
(comp setting 3)		tied to VINInternally fixed 2.25MHz200µF120µF100µF
Table 8-2 Switching Frequency and Compensation for TPS62812-EP (2A) and TPS62811-EP (1A)
COMPENSATIONRCFSWITCHING FREQUENCYMINIMUM OUTPUT CAPACITANCE
FOR VOUT < 1V		MINIMUM OUTPUT CAPACITANCE
FOR 1V ≤ VOUT < 3.3V		MINIMUM OUTPUT CAPACITANCE
FOR VOUT ≥ 3.3V
For the smallest output capacitance
(comp setting 1)		10kΩ ... 4.5kΩ1.8MHz (10kΩ) ... 4MHz (4.5kΩ)
according to Equation 1		30µF18µF15µF
For medium output capacitance
(comp setting 2)		33kΩ ... 15kΩ1.8MHz (33kΩ) ... 4MHz (15kΩ)
according to Equation 2		60µF36µF30µF
For large output capacitance
(comp setting 3)		100kΩ ... 45kΩ1.8MHz (100kΩ) ...4MHz (45kΩ)
according to Equation 3		130µF80µF68µF
For the smallest output capacitance
(comp setting 1)		tied to GNDInternally fixed 2.25MHz30µF18µF15µF
For large output capacitance
(comp setting 3)		tied to VINInternally fixed 2.25MHz130µF80µF68µF

Refer to Section 9.1.3.2 for further details on the required output capacitance required depending on the output voltage.

A too-high resistor value for RCF is decoded as tied to VIN. A value below the lowest range is decoded as tied to GND. The minimum output capacitance in Table 8-1 and Table 8-2 is for capacitors close to the output of the device. If the capacitance is distributed, a lower compensation setting can be required. All values are effective capacitance including, but not limited to:

  • All tolerances
  • Aging
  • DC bias effect