* Testing boost converter (5v to 5.5V) * Present about fanout board * Quick implemention way ## 1. Testing boost converter ![](https://i.imgur.com/3NgarGz.png) * No filter * ![](https://i.imgur.com/b2d2N9J.png) * With filter (20MHz) * ![](https://i.imgur.com/EzB5F27.png) ### 1.1 Summery: * Needs to consider how to design filter to eliminate spike ## 2. The Current State of FanOut-48 Boards * V1 board can't output negative voltage * Fatal problem * [Distrotion](https://hackmd.io/iEFjZ2p2TgOp4TjUZClLmw?view#Source-100KHz-15Vpp-FuncGen50-ohm) ### 2.1 Quick solution Swap output: GND <-> Vo_CH_n * Only output negatve voltage * Distortion is still not solved ### 2.2 Complete solution * Using 8ch-fanout board solution(ICs) * Apply above power soultion * DC-DC: USB 5V to +-5.5V or higher for LDO-in * For 5V output LDOs, input need > Vdrop at least * Vdrop ~300mV for modern MOSFET drived LDOs