User's Manual

FLC-BTM101 Datasheet
Flaircomm Microelectronics Confidential
-14-
4. Physical Interfaces
4.1 Power Supply
BTM101 contains two regulators:
 One switch-mode regulator, which generates the main supply rail directly from battery
 One low-voltage linear regulator with 1.2V output powers digital circuits
VDD_PIO is input voltage to power all digital I/Os including PIOs, UART port, SPI port and I2C.
4.2 Reset
The module may be reset from several sources:
Power-on reset
 Software configured watchdog timer.
4.2.1 Digital Pin States on Reset
The following table shows the digital pin states of BTM101 on reset. PU and PD default to weak
values unless specified otherwise.
Pin Name / Group
On Reset
I2C_SDA
Strong PU
I2C_SCL
Strong PU
PIO[11:0]
Weak PD
Table 3: Digital Pin Status on Reset
4.2.2 Power-on Reset
The following table shows how the power-on reset occurs.