TXB0108: High Capacitive Load

Hey Ryuji,

I think you'll be hard pressed to drive a load that large with this part, but fear not, there may be a work around. If you want to provide more drive then you can parallel two or more of the output lines together. If you do this you will need to ensure that the outputs that are tied together are driven by the same input signal on their respective input pins. Obviously the downside to this probably means having two, or more, translator IC.

Another option for you could be to add a series resistor on the output to increase the impedance. Although this would help with driving more capacitance, you're going to be hit with a performance decrease. This resistance will give you a RC circuit and will begin to limit the datarate. For you, this solution is not advised since you want to go 20MHz.

I'm glad you brought up the TXS series of devices. I was going to recommend you take a look at these since they can handle higher capacitive loads at the expense of minor speed hits. This ability to handle the higher capacitive loads working in tandem with two+ channels tied together I think is your best bet for driving your desired load.

Best Regards,
Nick

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