This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LSF0108: LSF0108 spi signal issue

Part Number: LSF0108
Other Parts Discussed in Thread: ADS7953, SN74AXC4T774, SN74AHCT125, SN74LVC1G34, SN74AHC1G125

hello 

     we are using the lsf0108 for spi level shift 3V3 to 5V,but on the 5v side,the pull up resistor is 4.7k,the clock(1.5MHz) rising edge is very slow, and the lowest  value of the high level is very low(about4.3V,figure1),if i change the pull up resistor to 2k,the max value of the low level is very high(about 0.7V,figure2),but the rising edge has not change.and i try to change 3.3V side resistor and it's not has improve.

the other signal of the spi group all like this

can you give me your advice

figure1 4.7k pull up 

figure 2  2.2k pull up

schematic