ZHCSCK8H May 2014 – April 2025 LP8860-Q1
PRODUCTION DATA
- 1
- 1 特性
- 2 應用
- 3 說明
- Device Comparison Table
- 4 Pin Configuration and Functions
-
5 Specifications
- 5.1 Absolute Maximum Ratings
- 5.2 ESD Ratings
- 5.3 Recommended Operating Conditions
- 5.4 Thermal Information
- 5.5 Electrical Characteristics
- 5.6 Current Sinks Electrical Characteristics
- 5.7 Boost Converter Characteristics
- 5.8 Logic Interface Characteristics
- 5.9 VIN Undervoltage Protection (VIN_UVLO)
- 5.10 VDD Undervoltage Protection (VDD_UVLO)
- 5.11 VIN Overvoltage Protection (VIN_OVP)
- 5.12 VIN Overcurrent Protection (VIN_OCP)
- 5.13 Power-Line FET Control Electrical Characteristics
- 5.14 External Temp Sensor Control Electrical Characteristics
- 5.15 I2C Serial Bus Timing Parameters (SDA, SCLK)
- 5.16 SPI Timing Requirements
- 5.17 Typical Characteristics
-
6 Detailed Description
- 6.1 Overview
- 6.2 Functional Block Diagram
- 6.3 Feature Description
- 6.4 Device Functional Modes
- 6.5 Programming
- 6.6
Register Maps
- 6.6.1
Register Bit Explanations
- 6.6.1.1 Display/Cluster1 Brightness Control MSB
- 6.6.1.2 Display/Cluster1 Brightness Control LSB
- 6.6.1.3 Display/Cluster1 Output Current MSB
- 6.6.1.4 Display/Cluster1 Output Current LSB
- 6.6.1.5 Cluster2 Brightness Control MSB
- 6.6.1.6 Cluster2 Brightness Control LSB
- 6.6.1.7 Cluster2 Output Current
- 6.6.1.8 Cluster3 Brightness Control MSB
- 6.6.1.9 Cluster3 Brightness Control LSB
- 6.6.1.10 Cluster3 Output Current
- 6.6.1.11 Cluster4 Brightness Control MSB
- 6.6.1.12 Cluster4 Brightness Control LSB
- 6.6.1.13 Cluster4 Output Current
- 6.6.1.14 Configuration
- 6.6.1.15 Status
- 6.6.1.16 Fault
- 6.6.1.17 LED Fault
- 6.6.1.18 Fault Clear
- 6.6.1.19 Identification
- 6.6.1.20 Temp MSB
- 6.6.1.21 Temp LSB
- 6.6.1.22 Display LED Current MSB
- 6.6.1.23 Display LED Current LSB
- 6.6.1.24 Display LED PWM MSB
- 6.6.1.25 Display LED PWM LSB
- 6.6.1.26 EEPROM Control
- 6.6.1.27 EEPROM Unlock Code
- 6.6.2
EEPROM Bit Explanations
- 6.6.2.1 EEPROM Register 0
- 6.6.2.2 EEPROM Register 1
- 6.6.2.3 EEPROM Register 2
- 6.6.2.4 EEPROM Register 3
- 6.6.2.5 EEPROM Register 4
- 6.6.2.6 EEPROM Register 5
- 6.6.2.7 EEPROM Register 6
- 6.6.2.8 EEPROM Register 7
- 6.6.2.9 EEPROM Register 8
- 6.6.2.10 EEPROM Register 9
- 6.6.2.11 EEPROM Register 10
- 6.6.2.12 EEPROM Register 11
- 6.6.2.13 EEPROM Register 12
- 6.6.2.14 EEPROM Register 13
- 6.6.2.15 EEPROM Register 14
- 6.6.2.16 EEPROM Register 15
- 6.6.2.17 EEPROM Register 16
- 6.6.2.18 EEPROM Register 17
- 6.6.2.19 EEPROM Register 18
- 6.6.2.20 EEPROM Register 19
- 6.6.2.21 EEPROM Register 20
- 6.6.2.22 EEPROM Register 21
- 6.6.2.23 EEPROM Register 22
- 6.6.2.24 EEPROM Register 23
- 6.6.2.25 EEPROM Register 24
- 6.6.1
Register Bit Explanations
-
7 Application and Implementation
- 7.1 Application Information
- 7.2
Typical Applications
- 7.2.1
Typical Application for Display Backlight
- 7.2.1.1 Design Requirements
- 7.2.1.2
Detailed Design Procedure
- 7.2.1.2.1 Inductor Selection
- 7.2.1.2.2 Output Capacitor Selection
- 7.2.1.2.3 Input Capacitor Selection
- 7.2.1.2.4 Charge Pump Output Capacitor
- 7.2.1.2.5 Charge Pump Flying Capacitor
- 7.2.1.2.6 Diode
- 7.2.1.2.7 Boost Converter Transistor
- 7.2.1.2.8 Boost Sense Resistor
- 7.2.1.2.9 Power Line Transistor
- 7.2.1.2.10 Input Current Sense Resistor
- 7.2.1.2.11 Filter Component Values
- 7.2.1.3 Application Performance Plots
- 7.2.2 Low VDD Voltage and Combined Output Mode Application
- 7.2.3 High Output Voltage Application
- 7.2.4 High Output Current Application
- 7.2.5 Three-Channel Configuration Without Serial Interface
- 7.2.6 Solution With Minimum External Components
- 7.2.1
Typical Application for Display Backlight
- 7.3 Power Supply Recommendations
- 7.4 Layout
- 8 Device and Documentation Support
- 9 Revision History
- 10Mechanical, Packaging, and Orderable Information
6.3.2.7 PWM Calculation Data Flow for Display Mode
Figure 6-9 shows the PWM calculation data flow for display mode. In PWM direct control mode most of the blocks are bypassed, and this flow chart does not apply.
Figure 6-9 PWM Data Flow CalculationTable 6-8 PWM Calculation Blocks
| BLOCK NAME | DESCRIPTION |
|---|---|
| PWM detector | PWM detector block measures the duty cycle of the input PWM signal. Resolution depends on the input signal frequency. Hysteresis selection sets the minimum allowable change to the input. Smaller changes are ignored. |
| Brightness register | 16-bit register for brightness setting <DISP_CL1_BRT[15:0]> |
| Brightness mode control | Brightness control block gets 16-bit value from the PWM detector, and also 16-bit value from the brightness register <DISP_CL1_BRT[15:0]>. <BRT_MODE[1:0]> selects whether to use PWM input duty cycle value, the brightness register value or multiplication. |
| Temperature regulator | Temperature regulator reduces LED PWM duty cycle depending on internal and external temperature sensor. See Section 6.3.9.2 and Section 6.3.9.3 for details |
| External temperature sensor | External NTC temperature sensor |
| Internal temperature sensor | Internal die temperature sensor |
| Sloper | Sloper makes the smooth transition from one brightness value to another. Slope time can be adjusted from 0 ms to 511 ms with <PWM_SLOPE[2:0]> EEPROM bits. |
| Advanced sloper | Advanced slope makes brightness changes smoother for eye; see Section 6.3.2.5 for details |
| PWM and Current Control | Hybrid PWM and Current dimming improves the optical efficiency of the LEDs by using PWM control with lower brightness values and current control with greater values. <EN_PWM_I> EEPROM bit enables Hybrid PWM and Current control. PWM dimming range can be set 12.5 to 50% of the brightness range with <GAIN_CTRL[2:0]> EEPROM bits. Current slope can be adjusted by using the <I_SLOPE[2:0]> EEPROM bits. See Section 6.3.2.6 for details |
| Dither | With dithering the output resolution can be further increased. This way the brightness change steps are not visible to eye. The amount of dithering is 0 to 4 bits, and is selected with <DITHER[2:0]> EEPROM bits. |
| PWM comparator | PWM comparator compares the PWM counter output to the value received from the dither block. Output of the PWM comparator directly controls the LED current sinks. If Phase Shift PWM (PSPWM) mode is used, the PWM counter values for each LED output are modified by summing an offset value to create different phases. |
| PWM counter | Overflowing 16-bit PWM counter creates new PWM cycle. Step for incrementation is defined by <PWM_FREQ[3:0]> and <PWM_RESOLUTION[1:0]> bits, see Table 6-3. |