ZHCSK37 August   2019 LP8867C-Q1 , LP8869C-Q1

PRODUCTION DATA.  

  1. 特性
    1.     简化原理图
  2. 应用
  3. 说明
    1.     系统效率
  4. 修订历史记录
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  7. Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics
    6. 7.6  Internal LDO Electrical Characteristics
    7. 7.7  Protection Electrical Characteristics
    8. 7.8  Current Sinks Electrical Characteristics
    9. 7.9  PWM Brightness Control Electrical Characteristics
    10. 7.10 Boost and SEPIC Converter Characteristics
    11. 7.11 Logic Interface Characteristics
    12. 7.12 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Integrated DC-DC Converter
        1. 8.3.1.1 DC-DC Converter Parameter Configuration
          1. 8.3.1.1.1 Switching Frequency
          2. 8.3.1.1.2 Spread Spectrum and External SYNC
          3. 8.3.1.1.3 Recommended Component Value and Internal Parameters
          4. 8.3.1.1.4 DC-DC Converter Switching Current Limit
          5. 8.3.1.1.5 DC-DC Converter Light Load Mode
        2. 8.3.1.2 Adaptive Voltage Control
          1. 8.3.1.2.1 Using Two-Divider
          2. 8.3.1.2.2 Using T-Divider
          3. 8.3.1.2.3 Feedback Capacitor
      2. 8.3.2 Internal LDO
      3. 8.3.3 LED Current Sinks
        1. 8.3.3.1 LED Output Configuration
        2. 8.3.3.2 LED Current Setting
        3. 8.3.3.3 Brightness Control
      4. 8.3.4 Protection and Fault Detections
        1. 8.3.4.1 Supply Fault and Protection
          1. 8.3.4.1.1 VIN Undervoltage Fault (VIN_UVLO)
          2. 8.3.4.1.2 VIN Overvoltage Fault (VIN_OVP)
        2. 8.3.4.2 Boost Fault and Protection
          1. 8.3.4.2.1 Boost Overvoltage Fault (BST_OVP)
          2. 8.3.4.2.2 SW Overvoltage Fault (SW_OVP)
        3. 8.3.4.3 LED Fault and Protection
          1. 8.3.4.3.1 LED Open Fault (LED_OPEN)
          2. 8.3.4.3.2 LED Short Fault (LED_SHORT)
        4. 8.3.4.4 Thermal Fault and Protection (TSD)
        5. 8.3.4.5 Overview of the Fault and Protection Schemes
    4. 8.4 Device Functional Modes
      1. 8.4.1 STANDBY State
      2. 8.4.2 SOFT START State
      3. 8.4.3 BOOST START State
      4. 8.4.4 NORMAL State
      5. 8.4.5 FAULT RECOVERY State
      6. 8.4.6 State Diagram and Timing Diagram for Start-up and Shutdown
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical Application for 4 LED Strings
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Inductor Selection
          2. 9.2.1.2.2 Output Capacitor Selection
          3. 9.2.1.2.3 Input Capacitor Selection
          4. 9.2.1.2.4 LDO Output Capacitor
          5. 9.2.1.2.5 Diode
        3. 9.2.1.3 Application Curves
      2. 9.2.2 SEPIC Mode Application
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Inductor
          2. 9.2.2.2.2 Diode
          3. 9.2.2.2.3 Capacitor C1
        3. 9.2.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12器件和文档支持
    1. 12.1 器件支持
      1. 12.1.1 开发支持
    2. 12.2 文档支持
      1. 12.2.1 相关文档
    3. 12.3 接收文档更新通知
    4. 12.4 社区资源
    5. 12.5 商标
    6. 12.6 静电放电警告
    7. 12.7 Glossary
  13. 13机械、封装和可订购信息

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

Pin Configuration and Functions

LP8867C-Q1 PWP Package
20-Pin HTSSOP With Exposed Thermal Pad
Top View
LP8867C-Q1 LP8869C-Q1 pin-01-LP8867C.gif
LP8869C-Q1 PWP Package
20-Pin HTSSOP With Exposed Thermal Pad
Top View
LP8867C-Q1 LP8869C-Q1 pin-02-LP8869C.gif

Pin Functions

PIN TYPE(1) DESCRIPTION
NO. NAME
1 VIN A Input power pin and pin for input voltage detection for OVP protection
2 LDO A Output of internal LDO; connect a 1-μF decoupling capacitor between this pin and noise-free GND. Put the capacitor as close to the chip as possible.
3 FSET A DC-DC (boost or SEPIC) switching frequency setting resistor; for normal operation, resistor value from 24 kΩ to 219 kΩ must be connected between this pin and ground.
4 VDDIO/EN I Enable input for the device as well as supply input (VDDIO) for digital pins.
5 FAULT OD Fault signal output. If unused, the pin may be left floating.
6 SYNC I Input for synchronizing DC-DC converter. If synchronization is not used, connect this pin to GND to disable spread spectrum or to VDDIO/EN to enable spread spectrum.
7 PWM I PWM dimming input.
8 NC No connect
9 GND G Ground
10 ISET A LED current setting resistor; for normal operation, resistor value from 20 kΩ to 129 kΩ must be connected between this pin and ground.
11 GND G Ground.
12 OUT4/GND A Current sink output for LP8867C-Q1
This pin must be connected to GND if not used.

GND pin for LP8869C-Q1

13 OUT3 A Current sink output.
This pin must be connected to GND if not used.
14 OUT2 A Current sink output.
This pin must be connected to GND if not used.
15 OUT1 A Current sink output.
This pin must be connected to GND if not used.
16 FB A DC-DC (boost or SEPIC) feedback input; for normal operation this pin must be connected to the middle of a resistor divider between VOUT and ground using feedback resistor values greater than 5kΩ.
17 PGND G DC-DC (boost or SEPIC) power ground.
18 SW A DC-DC (boost or SEPIC) switch pin.
19 NC No connect
20 VIN A Input power pin and pin for input voltage detection for OVP protection
A: Analog pin, G: Ground pin, P: Power pin, I: Input pin, I/O: Input/Output pin, O: Output pin, OD: Open Drain pin