JAJSEF5L July   2012  – May 2019 LP8556

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
    1.     概略回路図
  3. 3 概要
  4. 4 改訂履歴
  5. 5 Device Options
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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  Electrical Characteristics — Boost Converter
    7. 7.7  Electrical Characteristics — LED Driver
    8. 7.8  Electrical Characteristics — PWM Interface
    9. 7.9  Electrical Characteristics — Logic Interface
    10. 7.10 I2C Serial Bus Timing Parameters (SDA, SCL)
    11. 7.11 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Boost Converter
        1. 8.3.1.1 Boost Converter Operation
        2. 8.3.1.2 Setting Boost Switching Frequency
        3. 8.3.1.3 Output Voltage Control
          1. 8.3.1.3.1 Adaptive Control
          2. 8.3.1.3.2 Manual Control
        4. 8.3.1.4 EMI Reduction
      2. 8.3.2 Brightness Control
        1. 8.3.2.1  BRT_MODE = 00
        2. 8.3.2.2  BRT_MODE = 01
        3. 8.3.2.3  BRT_MODE = 10
        4. 8.3.2.4  BRT_MODE = 11
        5. 8.3.2.5  Output Dimming Schemes
          1. 8.3.2.5.1 PWM Control
          2. 8.3.2.5.2 Pure Current Control
          3. 8.3.2.5.3 Adaptive Control
        6. 8.3.2.6  Setting Full-Scale LED Current
        7. 8.3.2.7  Setting PWM Dimming Frequency
        8. 8.3.2.8  Phase Shift PWM Scheme
        9. 8.3.2.9  Slope and Advanced Slope
        10. 8.3.2.10 Dithering
      3. 8.3.3 Fault Detection
        1. 8.3.3.1 LED Fault Detection
          1. 8.3.3.1.1 Open Detect
          2. 8.3.3.1.2 Short Detect
        2. 8.3.3.2 Undervoltage Detection
        3. 8.3.3.3 Overcurrent Protection
        4. 8.3.3.4 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Active Mode
    5. 8.5 Programming
      1. 8.5.1 I2C-Compatible Serial Bus Interface
        1. 8.5.1.1 Interface Bus Overview
        2. 8.5.1.2 Data Transactions
        3. 8.5.1.3 Acknowledge Cycle
        4. 8.5.1.4 Acknowledge After Every Byte Rule
        5. 8.5.1.5 Addressing Transfer Formats
        6. 8.5.1.6 Control Register Write Cycle
        7. 8.5.1.7 Control Register Read Cycle
        8. 8.5.1.8 Register Read and Write Detail
    6. 8.6 Register Maps
      1. 8.6.1 Register Bit Explanations
        1. 8.6.1.1 Brightness Control
        2. 8.6.1.2 Device Control
        3. 8.6.1.3 Status
        4. 8.6.1.4 Direct Control
        5. 8.6.1.5 LED String Enable
      2. 8.6.2 EPROM Bit Explanations
        1. 8.6.2.1  LP8556TM (DSBGA) Configurations and Pre-Configured EPROM Settings
        2. 8.6.2.2  LP8556TM (DSBGA) Configurations and Pre-configured EPROM Settings Continued
        3. 8.6.2.3  LP8556SQ (WQFN) Configurations and Pre-configured EPROM Settings
        4. 8.6.2.4  CFG98
        5. 8.6.2.5  CFG9E
        6. 8.6.2.6  CFG0
        7. 8.6.2.7  CFG1
        8. 8.6.2.8  CFG2
        9. 8.6.2.9  CFG3
        10. 8.6.2.10 CFG4
        11. 8.6.2.11 CFG5
        12. 8.6.2.12 CFG6
        13. 8.6.2.13 CFG7
        14. 8.6.2.14 CFG9
        15. 8.6.2.15 CFGA
        16. 8.6.2.16 CFGE
        17. 8.6.2.17 CFGF
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Using LP8556 With I2C Host
        1. 9.1.1.1 Setting Boost Switching and PWM Dimming Frequencies
        2. 9.1.1.2 Setting Full-Scale LED Current
      2. 9.1.2 Using LP8556 With Configuration Resistors and IO Pins
        1. 9.1.2.1 Setting Boost Switching and PWM Dimming Frequencies
        2. 9.1.2.2 Setting Full-Scale LED Current
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Recommended Inductance for the Boost Power Stage
        2. 9.2.2.2 Recommended Capacitances for the Boost and LDO Power Stages
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 ドキュメントの更新通知を受け取る方法
    2. 12.2 コミュニティ・リソース
    3. 12.3 商標
    4. 12.4 静電気放電に関する注意事項
    5. 12.5 Glossary
  13. 13メカニカル、パッケージ、および注文情報

6 Pin Configuration and Functions

YFQ Package
20-Pin DSBGA
Top View
LP8556 30162677.gif
RTW Package
24-Pin WQFN
Top View
LP8556 30162675.gif
YFQ Package
20-Pin DSBGA
Bottom View
LP8556 30162678.gif
RTW Package
24-Pin WQFN
Bottom View
LP8556 30162672.gif

Pin Functions

PIN TYPE(1) DESCRIPTION
DSBGA WQFN NAME
A1, B1 1, 2 SW A A connection to the drain terminal of the integrated power MOSFET.
A2, B2 3, 4 GND_SW G A connection to the source terminal of the integrated power MOSFET.
A3 5 SDA I/O I2C data input/output pin
A4 6 SCL I I2C clock input pin
B3 9 PWM I PWM dimming input. Supply a 75-Hz to 25-kHz PWM signal to control dimming. This pin must be connected to GND if unused.
B4 7 EN / VDDIO P Dual-purpose pin serving both as a chip enable and as a power supply reference for PWM, SDA, and SCL inputs. Drive this pin with a logic gate capable of sourcing a minimum of 1 mA.
C1 22 VDD P Device power supply pin. Provide 2.7-V to 20-V supply to this pin. This pin is an input of the internal LDO regulator. The output of the internal LDO is what powers the device.
C2 20 VBOOST A Boost converter output pin. The internal feedback (FB) and overvoltage protection (OVP) circuitry monitors the voltage on this pin. Connect the converter output capacitor bank close to this pin.
C3 21 FSET A A connection for setting the boost frequency and PWM output dimming frequency by using an external resistor. Connect a resistor, RFSET, between this pin and the ground reference (see Table 5). This pin may be left floating if PWM_FSET_EN = 0 AND BOOST_FSET_EN = 0 (see Table 10).
C4 14 LED3 A LED driver - current sink terminal. If unused, it may be left floating.
D1 19 VLDO P Internal LDO output pin. Connect a capacitor, CVLDO, between this pin and the ground reference.
D2 23 ISET A A connection for the LED current set resistor. Connect a resistor, RISET, between this pin and the ground reference. This pin may be left floating if ISET_EN = 0 (see Table 10).
D3 10, 11, 15, 24, DAP GND I Ground pin.
D4 13 LED2 A LED driver - current sink pin. If unused, it may be left floating.
E1 18 LED6 A LED driver - current sink pin. If unused, it may be left floating.
E2 17 LED5 A LED driver - current sink pin. If unused, it may be left floating.
E3 16 LED4 A LED driver - current sink pin. If unused, it may be left floating.
E4 12 LED1 A LED driver - current sink pin. If unused, it may be left floating.
— 8 NC — No Connect pin.
(1) A: Analog Pin, G: Ground Pin, P: Power Pin, I: Digital Input Pin, I/O: Digital Input/Output Pin