ZHCSL09C April 2020 – December 2020 LM7480-Q1
PRODUCTION DATA
- 1 特性
- 2 應用
- 3 說明
- 4 Revision History
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
- 8 Parameter Measurement Information
- 9 Detailed Description
-
10Applications and Implementation
- 10.1 Application Information
- 10.2 Typical 12-V Reverse Battery Protection Application
- 10.3 200-V Unsuppressed Load Dump Protection Application
- 10.4 Do's and Don'ts
- 11Power Supply Recommendations
- 12Layout
- 13Device and Documentation Support
- 14Mechanical, Packaging, and Orderable Information
10.2.3.4 Hold-Up Capacitance
Usually bulk capacitors are placed on the output due to various reasons such as uninterrupted operation during power interruption or micro-short at the input, hold-up requirements for doing a memory dump before turning of the module and filtering requirements as well. This design considers minimum bulk capacitors requirements for meeting functional status "A" during LV124 E10 test case 2 100-μs input interruption. To achieve functional pass status A, acceptable voltage droop in the output of LM7480x-Q1 is based on the UVLO settings of downstream DC-DC converters. For this design, 2.5-V drop in output voltage for 100 μs is considered and the minimum hold-up capacitance required is calculated by
Minimum hold-up capacitance required for 2.5-V drop in 100 μs is 200 μF. Note that the typical application circuit shows the hold-up capacitor as optional because not all designs require hold-up capacitance.