Hello;
My Name is FATIH
I am using Wireless MBUS water meter scanning using S2LP and STM32L073. While making the PCB design, we applied the reference design value in the x-nucleo-s2868a2_schematic.pdf file exactly. However, although we see VDD voltage on Pin 1 on S2LP, SMPS voltage does not occur on Pin 2.
1. The SDN pin is grounded
2. We observed the 50 MHz oscillator output from the oscillator.
3. Main voltage supplies are ok
but we still cannot get analogue voltage output on pin 2 (SMPS1 Analog Output). therefore S2LP is not working.
But our circuit works if we make an external supply of 1.5VDC from pin 3. Data sending and receiving operations WMBUS telegrams are transmitted successfully.
Also; When we connected the x-nucleo-s2868a2 board with External SPI Cables through our microprocessor of our PCB, we observed that we saw the smps1 voltage on the board and observed that it worked smoothly.
What could be the reason for the SMPS 1 Voltage not working
I would be grateful if you could help me
Sincerely;
