LTE Standard Module Series
EC25 Mini PCIe Hardware Design
EC25_Mini_PCIe_Hardware_Design 23 / 79
Execute
AT+QSCLK=1
to enable sleep mode.
Ensure the DTR is kept at high level or be kept open.
The host’s USB bus, which is connected with the module’s USB interface, enters suspend state.
3.4.2. Airplane Mode
When the module enters airplane mode, the RF function will be disabled, and all AT commands related to
it will be inaccessible. For more details, please refer to
Chapter 3.10.3
.
3.5. Power Supply
The following table shows pin definition of VCC_3V3 pins and ground pins.
Table 6: Definition of VCC_3V3 and GND Pins
The typical supply voltage of EC25 Mini PCIe is 3.3V. In the 2G network, the input peak current may reach
2.7A during the transmitting time. Therefore, the power supply must be able to provide a rated output
current of 2.7A at least, and a bypass capacitor of no less than 470µF with low ESR should be used to
prevent the voltage from dropping. If the switching power supply is used to supply power to the module,
the power device and power supply routing traces of the switching power supply should avoid the
antennas as much as possible to prevent EMI interference.
The following figure shows a reference design of power supply where R2 and R3 are 1% tolerance
resistors and C3 is a low-ESR capacitor.
Pin Name
Pin No.
I/O
Power Domain
Description
VCC_3V3
2, 39, 41, 52
PI
3.0V~3.6V
Typically 3.3V DC supply
GND
4, 9, 15, 18, 21,
26, 27, 29, 34, 35,
37, 40, 43, 50
Mini card ground
