53L0-SATEL problem

[Davide Spina]

Posted on March 23, 2017 at 13:25

I'm having some troubles using the VL53L0X sensor (53L0-SATEL-I1 board); I used the other satellite board included in the x-nucleo-53L0A1 without any problems, but the 53L0-SATEL-I1 isn't working properly; it seems that the I2C bus is not available when i try to communicate with other sensors in the same bus. Using an oscilloscope i see that the voltage level in the sda and scl pin is about 1.5 Volts instead of 2.8V that should be thanks to the regulator and the level shifter. The input voltage of the 53L0-SATEL-I1 is about 3.3 Volts and in the output of the regulator i see 2.8 Volt correctly. The problem is in the SDA and SCL pin; the voltage is lower than the value should be. Could you please help me? Thanks. Davide 

#sensor #i2c

[John E KVAM]

Posted on March 30, 2017 at 20:02

David

The satellite board that came with your Nucleo expansion board is missing the level-shifter chip.

I'm assuming it was left off because they know what you are hooking it to.

The 53l0-Satel-l1satellite boards come with level shifters and should be more tolerant of voltages, not less.

So I tried this experiment:

Using a Nucleo and expansion board I attached both the satellite that comes with the expansion board (which is missing the level-shifter chip) AND the 53l0-Satel-l1. I then used the VL53L0-Expansion GUI software and tested. Both satellite boards work. (Hardest part is finding the 'device selection' box. It's in between the to large graphs.)

So I'm going to guess a hardware error. I connected the first 6 pins on the satellite board. Rumor has it one can connect XSDN to VDD, and by experiment I see that pin 1 (Int_Sensor) isn't required for this experiment. But other that that, it was just a straight-through connection.