User's Manual

H350 LGA Serials Module Hardware User Manual Page of
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Note:
 R8 is the current-limiting resistance in order to ensure VRTC working normally. R8 ≥1kohm

VRTC Current consumption < 2uA;
 C9 value can affect RTC hold time

You can refer to the following formula to calculate the RTC hold time: T= (1.8-0.5)*C/1=1.3C,
unit: s
For example: If C9 use 100uF capacitance, the RTC can hold about 130s.
Just don’t connect pin VRTC if no need RTC function.
5.2 ON/OFF and Reset
5.2.1 Pin Definition
H350 wireless communication module has three control signals: power on, off and reset the module.
Pin Definition:
Pin# Pin Name Electrical Level Description
45 POWER_OFF CMOS 1.8V Power off signal
47 POWER_ON CMOS 1.8V Power on signal
46 RESET_ALL_N CMOS 1.8V External reset signal input
5.2.2 Power ON Signal
After the module is powered on, users can lower down the POWER_ON signal, then module boots up.
The following table shows the burst timing:
Parameter Condition Minimum Value Typical Value Maximum Value Unit
Pulse Width 100 300 3000 ms
Timing control:
Figure 5- 2 Timing Control