Product Info

LTE Module Series
EC25 Mini PCIe Hardware Design
EC25_Mini_PCIe_Hardware_Design Confidential / Released 22 / 46
3.3. Power Supply
The following table shows pin definition of VCC_3V3 pins and ground pins.
Table 5: Definition of VCC_3V3 and GND Pins
The typical supply voltage of EC25 Mini PCIe is 3.3V. In the 2G networks, the input peak current may
reach to 2.7A during the transmitting time. Therefore, the power supply must be able to provide enough
current, and a bypass capacitor of no less than 470µF with low ESR should be used to prevent the
voltage from dropping.
The following figure shows a reference design of power supply. The precision of resistor R2 and R3 is 1%,
and the capacitor C3 needs a low ESR.
Figure 3: Reference Design of Power Supply
Pin No. Pin Name I/O Power Domain Description
2, 39, 41, 52 VCC_3V3 PI 3.0~3.6V 3.3V DC supply
4, 9, 15, 18, 21,
26, 27, 29, 34, 35,
37, 40, 43, 50
GND Mini card ground