The MMC/SDC can hot insertion/removal but some considerations to the host circuit are needed to avoid an incorrect operation. For example, if the system power supply (Vcc) is tied to the card socket directly, the Vcc will dip at the instant of contact closed due to a charge current to the capacitor that built in the card. 'A' in the right image is the scope view and it shows that occureing a voltage dip of about 600 millivolts. This is a sufficient level to trigger a brown out detector. 'B' in the right image shows that an inductor is inserted to block the surge current, the voltage dip is reduced to 200 millivoits. A low ESR capacitor, such as OS-CON, can eliminate the voltage dip dratiscally like shown in 'C'. However the low ESR capacitor can cause an oscillation of LDO regulator.
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Размещение рекламы на форуме способствует его дальнейшему развитию 
