Other Parts Discussed in Thread: BQ35100,
Tool/software:
Attached is a schematic of my project. I'm trying to communicate with the BQ35100 via I2C. The processor operates at 1.8V and the BQ35100 operates at VBAT which is 3.6V. Due to the different voltages I utilized the LSF0204 level shifter. The clock (SCL) on the 1.8V side of the level shifter operates as normal with a rise time of roughly 300nS. I'm able to communicate with an accelerometer on the 1.8V side with no issues. The clock (SCL) on the 3.6V side is far slower. I adjusted the pull up resistor as far as I could go before the communication stop functioning which was 2.15K. Even with a pull up of 2.15K, the rise time was 1.2uS. See attached image. Due to this slow rise time it is causing issues communicating with the BQ35100 as the maximum rise time is 300nS. Does the LSF0204 usually result in very slow rise times? What is the best way to correct this? Is there any adjustments that can be made?
