Other Parts Discussed in Thread: , TXS0104E
We used TI's PCA9306, but in actual use, we found that SDA1 was connected with our module's I2C_SDA, and the SDA level was 0.5-0.6v.
Lift the SDA1 pin of the chip to separate it from the PCB pad, and measure the voltage of 3V3 and 1V8 with the multimeter. The voltage values are all normal. The VFEF2 and EN pins of the chip use the voltage multimeter to measure the voltage of about 0.5v.R13 resistance was measured normally, and SDA1 was separately pulled up from 2.2k to 1V8. The voltage of SDA1 was measured to be about 0.6v.
1.In PCA9306EVM, VREF1 is connected with 0.01uf capacitor and VREF2 is connected with 100pF capacitor,My schematic USES a capacitance of 100nF. Does this affect it?
2.The voltage measurement of SDA2/SCL2 is 3.3v,SCL1 is 1.8v and SDA1 is 0.5v. What is the problem?
The schematic diagram is as follows: