Hello,
I am developing a Bluetooth device using the MSP430BT5190 + CC2560 (PAN1325) platform. In the documentation provided by Panasonic about the PAN1315 and PAN1325 modules, there is little (almost zero) information about the I/O supply voltage. In the electrical characteristics this value is required to be inside 1.62V-1.92V (1.8V nominal).
This requirement forces the system to include a 1.8V LDO. Moreover, if high data rates of the SPP are required, the MSP430BT5190 has to be supplied with higher voltage, and level shifters are required to interface the PAN1325 module. All this additional hardware may not be critical, but for sure increases the leakage current of the system reducing the battery lifetime of the device.
Now a curiosity. By mistake, I made the system work with all the VDD lines at 3.0V, including the VDDIO of the PAN1325 included in our device. For my surprise, the whole system is working properly. Actually, in many other ChipCon devices I have worked with, there was no such limitation in the VDDIO supply, which makes me question if there actually exists such restriction, or it is just a temporal specification in the Panasonic documentation (the available documentation is yet preliminary).
Does someone actually know if the CC2560 IO supply must be 1.8V or could be greater? If possible, I would like to avoid the inclusion of unnecessary LDO or level shifters connecting all the VDD lines directly to the battery.
