---
# System prepended metadata

title: Regular Meeting (2023.1.8)
tags: [Regular Meeting, DeWei]

---

# Regular Meeting (2023.1.8)

## New 48 fanout board

![](https://i.imgur.com/1twwcwG.png)

* Design: Finished
  * Remaining Power(Capacitor) should be verify
    * Power IC has Min and Max capacitor (even resistor is necessary) for stability
      * [LP5907](https://www.ti.com/lit/ds/symlink/lp5907.pdf)
        * 250 mA output current
        * Input Capacitor: No limited
        * Output Capacitor: 1 ~ 200uF
        * **Added Resistor for stability: 500m OHM** 
          * [ESR](https://en.wikipedia.org/wiki/Equivalent_series_resistance)
          * [Some old-fashion regulator needs ESR for stabality](https://electronics.stackexchange.com/questions/557056/why-recommend-tantalum-over-ceramic-capacitor-for-voltage-regulator)
        * No Soft-Start
      * [TPS7A20](https://www.ti.com/lit/ds/symlink/tps7a20.pdf)
        * 300 mA output current
        * Input Capacitor: No limited
        * Output Capacitor: 1 ~ 200uF (limited by soft-start capacitor)
        * Soft-Start
        * DT is too long from Mouser/Digikey (Ask other shopes)
      * [ADP125](https://www.analog.com/media/en/technical-documentation/data-sheets/adp124_125.pdf)
        * 500 mA output current
        * Input Capacitor: 1 uF
        * Output Capacitor: 1 uF (limited by soft-start capacitor)
        * **Added Resistor for stability: 1m ~ 1 OHM** 
        * Soft-Start
  * Stating layout
  * Ensure OPAs power input [MAX/MIN]capacitor

###### tags: `Regular Meeting` `DeWei`