SNVSB83B
June 2019 – January 2020
LP8867-Q1
,
LP8869-Q1
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Simplified Schematic
LED Backlight Efficiency
4
Revision History
5
Device Comparison Table
6
Pin Configuration and Functions
Pin Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Internal LDO Electrical Characteristics
7.7
Protection Electrical Characteristics
7.8
Current Sinks Electrical Characteristics
7.9
PWM Brightness Control Electrical Characteristics
7.10
Boost and SEPIC Converter Characteristics
7.11
Logic Interface Characteristics
7.12
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Integrated DC-DC Converter
8.3.1.1
DC-DC Converter Parameter Configuration
8.3.1.1.1
Switching Frequency
8.3.1.1.2
Spread Spectrum and External SYNC
8.3.1.1.3
Recommended Component Value and Internal Parameters
8.3.1.1.4
DC-DC Converter Switching Current Limit
8.3.1.1.5
DC-DC Converter Light Load Mode
8.3.1.2
Adaptive Voltage Control
8.3.1.2.1
Using Two-Divider
8.3.1.2.2
Using T-Divider
8.3.1.2.3
Feedback Capacitor
8.3.2
Internal LDO
8.3.3
LED Current Sinks
8.3.3.1
LED Output Configuration
8.3.3.2
LED Current Setting
8.3.3.3
Brightness Control
8.3.4
Power-Line FET Control
8.3.5
LED Current Dimming With External Temperature Sensor
8.3.6
Fault Detections and Protection
8.3.6.1
Supply Fault and Protection
8.3.6.1.1
VIN Undervoltage Fault (VIN_UVLO)
8.3.6.1.2
VIN Overvoltage Fault (VIN_OVP)
8.3.6.1.3
VIN Overcurrent Fault (VIN_OCP)
8.3.6.2
Boost Fault and Protection
8.3.6.2.1
Boost Overvoltage Fault (BST_OVP)
8.3.6.2.2
SW Overvoltage Fault (SW_OVP)
8.3.6.3
LED Fault and Protection (LED_OPEN and LED_SHORT)
8.3.6.4
Thermal Fault and Protection (TSD)
8.3.6.5
Overview of the Fault and Protection Schemes
8.4
Device Functional Modes
8.4.1
STANDBY State
8.4.2
SOFT START State
8.4.3
BOOST START State
8.4.4
NORMAL State
8.4.5
FAULT RECOVERY State
8.4.6
State Diagram and Timing Diagram for Start-up and Shutdown
9
Application and Implementation
9.1
Application Information
9.2
Typical Applications
9.2.1
Typical Application for 4 LED Strings
9.2.2
Design Requirements
9.2.3
Detailed Design Procedure
9.2.3.1
Inductor Selection
9.2.3.2
Output Capacitor Selection
9.2.3.3
Input Capacitor Selection
9.2.3.4
LDO Output Capacitor
9.2.3.5
Diode
9.2.4
Application Curves
9.2.5
SEPIC Mode Application
9.2.5.1
Design Requirements
9.2.5.2
Detailed Design Procedure
9.2.5.2.1
Inductor
9.2.5.2.2
Diode
9.2.5.2.3
Capacitor C1
9.2.5.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.2
Layout Example
12
Device and Documentation Support
12.1
Device Support
12.1.1
Development Support
12.2
Documentation Support
12.2.1
Related Documentation
12.3
Receiving Notification of Documentation Updates
12.4
Community Resources
12.5
Trademarks
12.6
Electrostatic Discharge Caution
12.7
Glossary
13
Mechanical, Packaging, and Orderable Information
封装选项
机械数据 (封装 | 引脚)
PWP|20
MHTS001G
散热焊盘机械数据 (封装 | 引脚)
PWP|20
PPTD027Z
订购信息
snvsb83b_oa
snvsb83b_pm
1
Features
AEC-Q100 Qualified for automotive applications:
Device temperature grade 1:
–40°C to +125°C, T
A
Functional safety capable
Documentation available to aid functional safety system design
3-, 4-Channel 120-mA current sinks
High dimming ratio of 10 000:1 at 100 Hz
Current matching 1% (typical)
LED String current up to 120 mA per channel
Outputs can be combined externally for higher current per string
Integrated boost and SEPIC converter for LED string power
Input voltage operating range 4.5 V to 40 V
Output voltage up to 45 V
Integrated 3.3-A Switch FET
Switching frequency 300 kHz to 2.2 MHz
Switching synchronization input
Spread spectrum for lower EMI
Fault detection and protection
Fault output
Input voltage OVP, UVLO and OCP
Boost block SW OVP and output OVP
LED open and short fault detection
Power-Line FET control for battery bus protection
Automatic LED current reduction with external temperature sensor
Thermal shutdown