Data Sheet

EMC3380 Series Wireless Module Data Manual
Copyright of Shanghai MXCHIP Information Technology Co., Ltd.
17
(1). Special function capture pins. When the module starts, it will detect the state of these pins to enter
special functions, please refer to section 3.2.3
(2). The default state of the pin. When the Reset button is pressed, all GPIO ports will maintain the previous
state. When the Reset button is released, the state of the GPIO returns to the state described in "Default State"
in Table 2. EfusePullCtrlx indicates that the default state of the pin is determined by the eFuse status bit is
determined.
(3). On the EMC3380A module, these pins are connected to the onboard audio noise reduction chip BR262,
while on the EMC3380 module, these pins are in a floating state /. The BR262 data sheet can be downloaded
athttps://www.onsemi.com/pub/Collateral/BR262-D.PDF. The connection circuit diagram on the module is as
follows:
Figure 3 Audio noise reduction chip BR262 connection schematic diagram
(4). The time from system power-on to GPIO power supply can be divided into three phases:
1. The power supply voltage rises to 1.5V, and the internal AON_LDO voltage rises to 0.5V.
Determined by 3.3V / 1.8V power-on time
2. The chip's internal analog circuit needs 6ms to power the Reset button, and then the digital circuit
starts to work.
3. After 300us～1.5ms, the GPIO is powered on, and the default level takes effect.
Phases 2 and 3 take a total of 6.3ms to 7.5ms.
Low energy pin definition
Low energy pins can wake the module from DeepSleep state, and they are located on the keyboard scan
function and touch function pins.
Table 3 Low energy pin definition
Pin
Number
Name
Function 28
(Ext32K)
Function 29
(key scan
row)
Function 30
(key scan col)
Function 31
(wakeup)
PX_FUNC_DE
FAULT
14
PA12
KEY_ROW0
LGPIO0
GPIOC_LP0
15
PA13
KEY_ROW1
LGPIO1
GPIOC_LP1
19
PA14
RTC_OUT
KEY_ROW2
LGPIO2
GPIOC_LP2
23
PA15
RTC
EXT_32K
KEY_ROW3
KEY_COL6
LGPIO3
GPIOC_LP3