UMTS/HSPA+ Module Series
UG89 Hardware Design
UG89_Hardware_Design 32 / 73
3.6.4.3. Overvoltage Shutdown*
The overvoltage shutdown threshold is the specified maximum supply voltage VBAT given in Table 23.
When the average supply voltage measured by UG89 approaches the overvoltage shutdown threshold
(i.e., 0.05V offset) the module will send the following URC:
^SBC: Overvoltage Warning
The overvoltage warning is sent only once until the next time the module is close to the overvoltage
shutdown threshold.
If the voltage continues to rise above the specified overvoltage shutdown threshold, the module will send
the following URC:
^SBC: Overvoltage Shutdown
This alert is sent only once before the module shuts down cleanly without sending any further messages.
This type of URC does not need to be activated by the user. It will be output automatically when fault
conditions occur.
“*” means under development.
3.7. UART Interfaces
The module provides two UART interfaces: the UART1 interface and the debug UART interface. The
features of these interfaces are shown below.
The UART1 interface supports 4800bps, 9600bps, 19200bps, 38400bps, 57600bps, 115200bps,
230400bps, 460800bps, 921600bps and 1Mbps baud rates, and the default is 115200bps. This
interface is used for data transmission and AT command communication.
The debug UART interface supports 115200bps baud rate. It is used for outputting partial logs.
The following tables show the pin definition of UART1 interface.
Table 11: Pin Definition of the UART1 Interface
Pin Name
Pin No.
I/O
Description
Comment
UART1_RI
13
DO
Ring indication
1.8V power domain.
If unused, keep open.
UART1_DCD
45
DO
Data carrier detection
NOTE