ZHCSH29B April   2017  – December 2018 LP87524B-Q1 , LP87524J-Q1 , LP87524P-Q1

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
    1.     简化原理图
  3. 3 说明
    1.     效率与输出电流间的关系
  4. 4 修订历史记录
    1.     Device Images
  5. 5 Pin Configuration and Functions
    1.     Pin 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 I2C Serial Bus Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Descriptions
      1. 7.3.1 DC-DC Converters
        1. 7.3.1.1 Overview
        2. 7.3.1.2 Transition Between PWM and PFM Modes
        3. 7.3.1.3 Buck Converter Load-Current Measurement
        4. 7.3.1.4 Spread-Spectrum Mode
      2. 7.3.2 Sync Clock Functionality
      3. 7.3.3 Power-Up
      4. 7.3.4 Regulator Control
        1. 7.3.4.1 Enabling and Disabling Regulators
        2. 7.3.4.2 Changing Output Voltage
      5. 7.3.5 Enable and Disable Sequences
      6. 7.3.6 Device Reset Scenarios
      7. 7.3.7 Diagnosis and Protection Features
        1. 7.3.7.1 Power-Good Information (PGOOD pin)
        2. 7.3.7.2 Warnings for Diagnosis (Interrupt)
          1. 7.3.7.2.1 Output Power Limit
          2. 7.3.7.2.2 Thermal Warning
        3. 7.3.7.3 Protection (Regulator Disable)
          1. 7.3.7.3.1 Short-Circuit and Overload Protection
          2. 7.3.7.3.2 Overvoltage Protection
          3. 7.3.7.3.3 Thermal Shutdown
        4. 7.3.7.4 Fault (Power Down)
          1. 7.3.7.4.1 Undervoltage Lockout
      8. 7.3.8 GPIO Signal Operation
      9. 7.3.9 Digital Signal Filtering
    4. 7.4 Device Functional Modes
      1. 7.4.1 Modes of Operation
    5. 7.5 Programming
      1. 7.5.1 I2C-Compatible Interface
        1. 7.5.1.1 Data Validity
        2. 7.5.1.2 Start and Stop Conditions
        3. 7.5.1.3 Transferring Data
        4. 7.5.1.4 I2C-Compatible Chip Address
        5. 7.5.1.5 Auto-Increment Feature
    6. 7.6 Register Maps
      1. 7.6.1 Register Descriptions
        1. 7.6.1.1  OTP_REV
        2. 7.6.1.2  BUCK0_CTRL1
        3. 7.6.1.3  BUCK1_CTRL1
        4. 7.6.1.4  BUCK2_CTRL1
        5. 7.6.1.5  BUCK3_CTRL1
        6. 7.6.1.6  BUCK0_VOUT
        7. 7.6.1.7  BUCK0_FLOOR_VOUT
        8. 7.6.1.8  BUCK1_VOUT
        9. 7.6.1.9  BUCK1_FLOOR_VOUT
        10. 7.6.1.10 BUCK2_VOUT
        11. 7.6.1.11 BUCK2_FLOOR_VOUT
        12. 7.6.1.12 BUCK3_VOUT
        13. 7.6.1.13 BUCK3_FLOOR_VOUT
        14. 7.6.1.14 BUCK0_DELAY
        15. 7.6.1.15 BUCK1_DELAY
        16. 7.6.1.16 BUCK2_DELAY
        17. 7.6.1.17 BUCK3_DELAY
        18. 7.6.1.18 GPIO2_DELAY
        19. 7.6.1.19 GPIO3_DELAY
        20. 7.6.1.20 RESET
        21. 7.6.1.21 CONFIG
        22. 7.6.1.22 INT_TOP1
        23. 7.6.1.23 INT_TOP2
        24. 7.6.1.24 INT_BUCK_0_1
        25. 7.6.1.25 INT_BUCK_2_3
        26. 7.6.1.26 TOP_STAT
        27. 7.6.1.27 BUCK_0_1_STAT
        28. 7.6.1.28 BUCK_2_3_STAT
        29. 7.6.1.29 TOP_MASK1
        30. 7.6.1.30 TOP_MASK2
        31. 7.6.1.31 BUCK_0_1_MASK
        32. 7.6.1.32 BUCK_2_3_MASK
        33. 7.6.1.33 SEL_I_LOAD
        34. 7.6.1.34 I_LOAD_2
        35. 7.6.1.35 I_LOAD_1
        36. 7.6.1.36 PGOOD_CTRL1
        37. 7.6.1.37 PGOOD_CTRL2
        38. 7.6.1.38 PGOOD_FLT
        39. 7.6.1.39 PLL_CTRL
        40. 7.6.1.40 PIN_FUNCTION
        41. 7.6.1.41 GPIO_CONFIG
        42. 7.6.1.42 GPIO_IN
        43. 7.6.1.43 GPIO_OUT
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 Inductor Selection
        2. 8.2.1.2 Input Capacitor Selection
        3. 8.2.1.3 Output Capacitor Selection
        4. 8.2.1.4 Snubber Components
        5. 8.2.1.5 Supply Filtering Components
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 第三方产品免责声明
    2. 11.2 接收文档更新通知
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 术语表
  12. 12机械、封装和可订购信息

封装选项

请参考 PDF 数据表获取器件具体的封装图。

机械数据 (封装 | 引脚)
  • RNF|26
散热焊盘机械数据 (封装 | 引脚)
订购信息

7.3.4.1 Enabling and Disabling Regulators

The regulator(s) can be enabled when the device is in STANDBY or ACTIVE state. There are two ways for enable and disable the regulators:

  • Using EN_BUCKx bit in BUCKx_CTRL1 register (EN_PIN_CTRLx register bit is 0)
  • Using EN1/2/3 control pins (EN_BUCKx bit is 1 AND EN_PIN_CTRLx register bit is 1 in BUCKx_CTRL1 register)

If the EN1/2/3 control pins are used for enable and disable then the control pin is selected with BUCKx_EN_PIN_SELECT[1:0] bits (in BUCKx_CTRL1 register). The delay from the control signal rising edge to enabling of the regulator is set by BUCKx_STARTUP_DELAY[3:0] bits and the delay from control signal falling edge to disabling of the regulator is set by BUCKx_SHUTDOWN_DELAY[3:0] bits in BUCKx_DELAY register. The delays are valid only for EN1/2/3 signal control. The control with EN_BUCKx bit is immediate without the delays.

The control of the regulator (with 0-ms delays) is shown in Table 3.

NOTE

The control of the regulator cannot be changed from one ENx pin to a different ENx pin because the control is ENx signal edge sensitive. The control from ENx pin to register bit and back to the original ENx pin can be done during operation.

Table 3. Regulator Control

CONTROL METHOD EN_BUCKx EN_PIN_CTRLx BUCKx_EN_PIN_SELECT[1:0] EN_ROOF_FLOOR x EN1 PIN EN2 PIN EN3 PIN BUCKx
OUTPUT VOLTAGE
Enable/disable control with EN_BUCKx bit 0 Don't Care Don't Care Don't Care Don't Care Don't Care Don't Care Disabled
1 0 Don't Care Don't Care Don't Care Don't Care Don't Care BUCKx_VSET[7:0]
Enable/disable control with EN1 pin 1 1 00 0 Low Don't Care Don't Care Disabled
1 1 00 0 High Don't Care Don't Care BUCKx_VSET[7:0]
Enable/disable control with EN2 pin 1 1 01 0 Don't Care Low Don't Care Disabled
1 1 01 0 Don't Care High Don't Care BUCKx_VSET[7:0]
Enable/disable control with EN3 pin 1 1 10 0 Don't Care Don't Care Low Disabled
1 1 10 0 Don't Care Don't Care High BUCKx_VSET[7:0]
Roof/floor control with EN1 pin 1 1 00 1 Low Don't Care Don't Care BUCKx_FLOOR_VSET[7:0]
1 1 00 1 High Don't Care Don't Care BUCKx_VSET[7:0]
Roof/floor control with EN2 pin 1 1 01 1 Don't Care Low Don't Care BUCKx_FLOOR_VSET[7:0]
1 1 01 1 Don't Care High Don't Care BUCKx_VSET[7:0]
Roof/floor control with EN3 pin 1 1 10 1 Don't Care Don't Care Low BUCKx_FLOOR_VSET[7:0]
1 1 10 1 Don't Care Don't Care High BUCKx_VSET[7:0]

The regulator is enabled by the ENx pin or by I2C writing as shown in Figure 8. The soft-start circuit limits the in-rush current during start-up. When the output voltage rises to 0.35-V level, the output voltage becomes slew-rate controlled. If there is a short circuit at the output and the output voltage does not increase above 0.35-V level in 1 ms, the regulator is disabled, and interrupt is set. When the output voltage reaches the Power-Good threshold level the BUCKx_PG_INT interrupt flag (in INT_BUCK_x register) is set. The Power-Good interrupt flag can be masked using BUCKx_PG_MASK bit (in BUCKx_MASK register).

The ENx input pins have integrated pulldown resistors. The pulldown resistors are enabled by default, and the host can disable those with ENx_PD bits (in CONFIG register).

LP87524B-Q1 LP87524J-Q1 LP87524P-Q1 Enable_Disable_LP8752_38.gifFigure 8. Regulator Enable and Disable