SNVSBU3
March 2021
LP87702
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
I2C Serial Bus Timing Parameters
6.7
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Descriptions
7.3.1
Step-Down DC/DC Converters
7.3.1.1
Overview
7.3.1.2
Transition Between PWM and PFM Modes
7.3.1.3
Buck Converter Load Current Measurement
7.3.2
Boost Converter
7.3.3
Spread-Spectrum Mode
7.3.4
Sync Clock Functionality
7.3.5
Power-Up
7.3.6
Buck and Boost Control
7.3.6.1
Enabling and Disabling Converters
7.3.6.2
Changing Buck Output Voltage
7.3.7
Enable and Disable Sequences
7.3.8
Window Watchdog
7.3.9
Device Reset Scenarios
7.3.10
Diagnostics and Protection Features
7.3.10.1
Voltage Monitorings
7.3.10.2
Interrupts
7.3.10.3
Power-Good Information to Interrupt, PG0, and PG1 Pins
7.3.10.3.1
PGx Pin Gated (Unusual) Mode
7.3.10.3.2
PGx Pin Operation in Continuous Mode
7.3.10.3.3
Summary of PG0, PG1 Gated, and Continuous Operating Modes
7.3.10.4
Warning Interrupts for System Level Diagnostics
7.3.10.4.1
Output Power Limit
7.3.10.4.2
Thermal Warning
7.3.10.5
Protections Causing Converter Disable
7.3.10.5.1
Short-Circuit and Overload Protection
7.3.10.5.2
Overvoltage Protection
7.3.10.5.3
Thermal Shutdown
7.3.10.6
Protections Causing Device Power Down
7.3.10.6.1
Undervoltage Lockout
7.3.11
OTP Error Correction
7.3.12
Operation of GPO Signals
7.3.13
Digital Signal Filtering
7.4
Device Functional Modes
7.4.1
Modes of Operation
7.5
Programming
7.5.1
I2C-Compatible Interface
7.5.1.1
Data Validity
7.5.1.2
Start and Stop Conditions
7.5.1.3
Transferring Data
7.5.1.4
I2C-Compatible Chip Address
7.5.1.5
Auto Increment Feature
7.6
Register Maps
7.6.1
Register Descriptions
7.6.1.1
LP8770_map Registers
8
Application and Implementation
8.1
Application Information
8.2
Typical Application
8.2.1
Design Requirements
8.2.2
Detailed Design Procedure
8.2.2.1
Application Components
8.2.2.1.1
Inductor Selection
8.2.2.1.2
Buck Input Capacitor Selection
8.2.2.1.3
Buck Output Capacitor Selection
8.2.2.1.4
Boost Input Capacitor Selection
8.2.2.1.5
Boost Output Capacitor Selection
8.2.2.1.6
Supply Filtering Components
8.2.3
Current Limit vs Maximum Output Current
8.2.4
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.2
Layout Example
11
Device and Documentation Support
11.1
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
QFND590
Orderable Information
snvsbu3_oa
snvsbu3_pm
8.2.1
Design Requirements
Table 8-1 Design Parameters
DESIGN PARAMETER
EXAMPLE VALUE
Input voltage
3.3 V
Output voltages
1.8 V, 1.24 V, 5 V
Switching frequency
4 MHz