SNVSBY8
March 2021
TPS92391
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics
6.6
Logic Interface Characteristics
6.7
Timing Requirements for I2C Interface
14
6.8
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Control Interface
7.3.2
Function Setting
7.3.3
Device Supply (VDD)
7.3.4
Enable (EN)
7.3.5
Charge Pump
7.3.6
Boost Controller
7.3.6.1
Boost Cycle-by-Cycle Current Limit
7.3.6.2
Controller Min On/Off Time
7.3.6.3
Boost Adaptive Voltage Control
7.3.6.3.1
FB Divider Using Two-Resistor Method
7.3.6.3.2
FB Divider Using Three-Resistor Method
7.3.6.3.3
FB Divider Using External Compensation
7.3.6.4
Boost Sync and Spread Spectrum
7.3.6.5
Light Load Mode
7.3.7
LED Current Sinks
7.3.7.1
LED Output Current Setting
7.3.7.2
LED Output String Configuration
7.3.7.3
LED Output PWM Clock Generation
7.3.8
Brightness Control
7.3.8.1
Brightness Control Signal Path
7.3.8.2
Dimming Mode
7.3.8.3
LED Dimming Frequency
7.3.8.4
Phase-Shift PWM Mode
7.3.8.5
Hybrid Mode
7.3.8.6
Direct PWM Mode
7.3.8.7
Sloper
7.3.8.8
PWM Detector Hysteresis
7.3.8.9
Dither
7.3.9
Protection and Fault Detections
7.3.9.1
Supply Faults
7.3.9.1.1
VIN Undervoltage Faults (VINUVLO)
51
7.3.9.1.2
VIN Overvoltage Faults (VINOVP)
7.3.9.1.3
VDD Undervoltage Faults (VDDUVLO)
7.3.9.1.4
VIN OCP Faults (VINOCP)
7.3.9.1.4.1
VIN OCP Current Limit vs. Boost Cycle-by-Cycle Current Limit
7.3.9.1.5
Charge Pump Faults (CPCAP, CP)
7.3.9.1.6
CRC Error Faults (CRCERR)
7.3.9.2
Boost Faults
7.3.9.2.1
Boost Overvoltage Faults (BSTOVPL, BSTOVPH)
7.3.9.2.2
Boost Overcurrent Faults (BSTOCP)
7.3.9.2.3
LEDSET Resistor Missing Faults (LEDSET)
7.3.9.2.4
MODE Resistor Missing Faults (MODESEL)
7.3.9.2.5
FSET Resistor Missing Faults (FSET)
7.3.9.2.6
ISET Resistor Out of Range Faults (ISET)
7.3.9.2.7
Thermal Shutdown Faults (TSD)
7.3.9.3
LED Faults
7.3.9.3.1
Open LED Faults (OPEN_LED)
7.3.9.3.2
Short LED Faults (SHORT_LED)
7.3.9.3.3
LED Short to GND Faults (GND_LED)
7.3.9.3.4
Invalid LED String Faults (INVSTRING)
7.3.9.3.5
I2C Timeout Faults
7.3.9.4
Overview of the Fault and Protection Schemes
7.4
Device Functional Modes
7.4.1
State Diagram
7.4.2
Shutdown
7.4.3
Device Initialization
7.4.4
Standby Mode
7.4.5
Power-line FET Soft Start
7.4.6
Boost Start-Up
7.4.7
Normal Mode
7.4.8
Fault Recovery
7.4.9
Latch Fault
7.4.10
Start-Up Sequence
7.5
Programming
7.5.1
I2C-Compatible Interface
7.5.2
Programming Examples
7.5.2.1
General Configuration Registers
7.5.2.2
Clearing Fault Interrupts
7.5.2.3
Disabling Fault Interrupts
7.5.2.4
Diagnostic Registers
7.6
Register Maps
7.6.1
FullMap Registers
8
Application and Implementation
8.1
Application Information
8.2
Typical Applications
8.2.1
Full Feature Application for Display Backlight
8.2.1.1
Design Requirements
8.2.1.2
Detailed Design Procedure
8.2.1.2.1
Inductor Selection
8.2.1.2.2
Output Capacitor Selection
8.2.1.2.3
Input Capacitor Selection
8.2.1.2.4
Charge Pump Output Capacitor
8.2.1.2.5
Charge Pump Flying Capacitor
8.2.1.2.6
Output Diode
8.2.1.2.7
Switching FET
8.2.1.2.8
Boost Sense Resistor
8.2.1.2.9
Power-Line FET
8.2.1.2.10
Input Current Sense Resistor
8.2.1.2.11
Feedback Resistor Divider
8.2.1.2.12
Critical Components for Design
8.2.1.3
Application Curves
8.2.2
Application With Basic/Minimal Operation
8.2.2.1
Design Requirements
8.2.2.2
Detailed Design Procedure
8.2.2.3
Application Curves
8.2.3
SEPIC Mode Application
8.2.3.1
Design Requirements
8.2.3.2
Detailed Design Procedure
8.2.3.2.1
Inductor Selection
8.2.3.2.2
Coupling Capacitor Selection
8.2.3.2.3
Output Capacitor Selection
8.2.3.2.4
Input Capacitor Selection
8.2.3.2.5
Charge Pump Output Capacitor
8.2.3.2.6
Charge Pump Flying Capacitor
8.2.3.2.7
Switching FET
8.2.3.2.8
Output Diode
8.2.3.2.9
Switching Sense Resistor
8.2.3.2.10
Power-Line FET
8.2.3.2.11
Input Current Sense Resistor
8.2.3.2.12
Feedback Resistor Divider
8.2.3.2.13
Critical Components for Design
8.2.3.3
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
11
Device and Documentation Support
11.1
Device Support
11.1.1
Third-Party Products Disclaimer
11.2
Receiving Notification of Documentation Updates
11.3
Support Resources
11.4
Trademarks
11.5
Electrostatic Discharge Caution
11.6
Glossary
12
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
RHB|32
MPQF130D
Thermal pad, mechanical data (Package|Pins)
RHB|32
QFND029X
Orderable Information
snvsby8_oa
snvsby8_pm
1
Features
Input voltage operating range 3 V to 48 V
Six
high-precision current sinks
Up to
200
-mA DC current for each current sink
Current matching 1% (typical)
Dimming ratio 32 000:1 using 152-Hz LED output PWM frequency
Up to 16-bit LED dimming resolution with I2C, or PWM input
8 Configurable LED strings configuration
Auto-phase shift PWM dimming
12-bit Analog dimming
Switching frequency 100 kHz to 2.2 MHz
Boost spread spectrum for reduced EMI
Boost sync input to set boost switching frequency from an external clock
Up to 48-V V
OUT
boost or SEPIC DC/DC controller
Switching frequency 100 kHz to 2.2 MHz
Boost spread spectrum for reduced EMI
Boost sync input to set boost switching frequency from an external clock
Extensive fault diagnostics