TXS0108E: B side Low level problems.

Part Number: TXS0108E


I use to TSX0108E level Shifter.

VCCA = 3.3V  A side connected for FPGA.

VCCB = 5V B side connected for some communication chip.(i can't tell you the name of chip. sorry)

the problem is coming from B side.

B side connected signal  state default is High. it is a Clk signal 4.8kHz.

I want this signal to operate from 5 v to 0 v, operating at 5 v to 2.5v.

Sometimes, at the beginning of the low descent, it behaves like 0v, but again, it behaves as if it were 2.5v.

like this.

What I suspect is the falling time of the signal.The falling time is approximately 250 ns.

The current phenomenon is solved by using the 51k Pull-Down Resistance, but I wonder if it is reliable.

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