SNOSDE8A
July 2023 – September 2023
LM74912-Q1
PRODUCTION DATA
1
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
Switching Characteristics
6.7
Typical Characteristics
7
Parameter Measurement Information
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Charge Pump
8.3.2
Dual Gate Control (DGATE, HGATE)
8.3.2.1
Reverse Battery Protection (A, C, DGATE)
8.3.2.2
Load Disconnect Switch Control (HGATE, OUT)
8.3.3
Short Circuit Protection (CS+, CS-, ISCP)
8.3.4
Overvoltage Protection and Battery Voltage Sensing (SW, OV, UVLO)
8.3.5
Low IQ SLEEP Mode (SLEEP, SLEEP_OV)
8.4
Device Functional Modes
9
Applications and Implementation
9.1
Application Information
9.2
Typical 12-V Reverse Battery Protection Application
9.2.1
Design Requirements for 12-V Battery Protection
9.2.2
Automotive Reverse Battery Protection
9.2.2.1
Input Transient Protection: ISO 7637-2 Pulse 1
9.2.2.2
AC Super Imposed Input Rectification: ISO 16750-2 and LV124 E-06
9.2.2.3
Input Micro-Short Protection: LV124 E-10
9.2.3
Detailed Design Procedure
9.2.3.1
Design Considerations
9.2.3.2
Charge Pump Capacitance VCAP
9.2.3.3
Input , Supply and Output Capacitance
9.2.3.4
Hold-Up Capacitance
9.2.3.5
Overvoltage Protection and Battery Monitor
9.2.3.6
Selecting Short Circuit Current Threshold
9.2.3.6.1
Selection of Scaling Resistor RSET and RISCP for Short Circuit Protection
9.2.4
MOSFET Selection: Blocking MOSFET Q1
9.2.5
MOSFET Selection: Hot-Swap MOSFET Q2
9.2.6
TVS Selection
9.2.7
Application Curves
9.3
Best Design Practices
9.4
Power Supply Recommendations
9.4.1
Transient Protection
9.4.2
TVS Selection for 12-V Battery Systems
9.4.3
TVS Selection for 24-V Battery Systems
9.5
Layout
9.5.1
Layout Guidelines
9.5.2
Layout Example
10
Device and Documentation Support
10.1
Receiving Notification of Documentation Updates
10.2
Support Resources
10.3
Trademarks
10.4
Electrostatic Discharge Caution
10.5
Glossary
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
RGE|24
MPQF124G
Thermal pad, mechanical data (Package|Pins)
RGE|24
QFND703
Orderable Information
snosde8a_oa
snosde8a_pm
1
Features
AEC-Q100 qualified for automotive applications
Device temperature grade 1:
–40°C to +125°C ambient operating temperature range
Functional Safety-Capable
Documentation available to aid functional safety system design
3-V to 65-V input range
Reverse input protection down to –65 V
Drives external back-to-back N-channel MOSFETs in common drain configuration
Ideal diode operation with 10.5-mV A to C forward voltage drop regulation
Low reverse detection threshold (–10.5 mV) with fast response (0.5 µs)
20-mA peak gate (DGATE) turn-on current
2.6-A peak DGATE turn-off current
Adjustable overvoltage and undervoltage protection
Output short circuit protection with MOSFET latched off state
Ultra low power mode with 2.5-µA shutdown current (EN=Low)
SLEEP mode with 6-µA current (EN=High, SLEEP=Low)
Meets automotive ISO7637 transient requirements with a suitable transient voltage suppressor (TVS) diode
Available in 4 mm × 4 mm 24-pin VQFN package