ZHCSQI6A May   2022  – July 2022 TPS62870-Q1 , TPS62871-Q1 , TPS62872-Q1 , TPS62873-Q1

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  5. 说明(续)
  6. Device Options
  7. Pin Configuration and Functions
  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 I2C Interface Timing Characteristics
    7. 8.7 Timing Requirements
    8. 8.8 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Fixed-Frequency DCS Control Topology
      2. 9.3.2  Forced PWM and Power Save Modes
      3. 9.3.3  Precise Enable
      4. 9.3.4  Start-Up
      5. 9.3.5  Switching Frequency Selection
      6. 9.3.6  Output Voltage Setting
        1. 9.3.6.1 Output Voltage Range
        2. 9.3.6.2 Output Voltage Setpoint
        3. 9.3.6.3 Non-Default Output Voltage Setpoint
        4. 9.3.6.4 Dynamic Voltage Scaling
      7. 9.3.7  Compensation (COMP)
      8. 9.3.8  Mode Selection and Clock Synchronization (MODE/SYNC)
      9. 9.3.9  Spread Spectrum Clocking (SSC)
      10. 9.3.10 Output Discharge
      11. 9.3.11 Undervoltage Lockout (UVLO)
      12. 9.3.12 Overvoltage Lockout (OVLO)
      13. 9.3.13 Overcurrent Protection
        1. 9.3.13.1 Cycle-by-Cycle Current Limiting
        2. 9.3.13.2 Hiccup Mode
        3. 9.3.13.3 Current Limit Mode
      14. 9.3.14 Power Good (PG)
        1. 9.3.14.1 Standalone or Primary Device Behavior
        2. 9.3.14.2 Secondary Device Behavior
      15. 9.3.15 Remote Sense
      16. 9.3.16 Thermal Warning and Shutdown
      17. 9.3.17 Stacked Operation
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power-On Reset
      2. 9.4.2 Undervoltage Lockout
      3. 9.4.3 Standby
      4. 9.4.4 On
    5. 9.5 Programming
      1. 9.5.1 Serial Interface Description
      2. 9.5.2 Standard, Fast, Fast Mode Plus Protocol
      3. 9.5.3 I2C Update Sequence
    6. 9.6 Register Map
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Selecting the Inductor
        2. 10.2.2.2 Selecting the Input Capacitors
        3. 10.2.2.3 Selecting the Compensation Resistor
        4. 10.2.2.4 Selecting the Output Capacitors
        5. 10.2.2.5 Selecting the Compensation Capacitor, CC
        6. 10.2.2.6 Selecting the Compensation Capacitor, CC2
      3. 10.2.3 Application Curves
    3. 10.3 Best Design Practices
    4. 10.4 Power Supply Recommendations
    5. 10.5 Layout
      1. 10.5.1 Layout Guidelines
      2. 10.5.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 第三方产品免责声明
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 接收文档更新通知
    4. 11.4 支持资源
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 术语表
  12. 12Mechanical, Packaging, and Orderable Information

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

Switching Frequency Selection

During device initialization, a resistor-to-digital converter in the device determines the state of the FSEL pin and sets the switching frequency of the DC/DC converter according to Table 9-2.

Table 9-2 Switching Frequency Options
Resistor at FSEL (1%)Switching Frequency
Short to GND1.5 MHz
6.2 kΩ to GND2.25 MHz
47 kΩ to VIN2.5 MHz
Short to VIN3 MHz

Figure 9-10 shows a simplified block diagram of the R2D converter used to detect the state of the FSEL pin (an identical circuit detects the state of the VSEL pin – see Section 9.3.6.2).



Figure 9-10 FSEL R2D Converter Functional Block Diagram

Detection of the state of the FSEL pin works as follows:

To detect the most significant bit (MSB), the circuit opens S1 and S2, and the input buffer detects if a high or a low level is connected to the FSEL pin.

To detect the least significant bit (LSB):

  • If the MSB was 0, the circuit closes S1. If the input buffer detects a high level, LSB = 1. If the circuit detects a low level, LSB = 0.
  • If the MSB was 1, the circuit closes S2. If the input buffer detects a low level, LSB = 0. If the circuit detects a high level, LSB = 1.

The propagation delay of the current-sensing comparator limits the minimum on time of the device, meaning the maximum switching frequency the device can support decreases with small duty cycles. Figure 8-5 shows the practical operating range of the device with 3.3-V and 5-V supplies.