User's Manual

LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design Confidential / Released 16 / 94
The following figure shows a block diagram of EC21 and illustrates the major functional parts.
 Power management
 Baseband
 DDR+NAND flash
 Radio frequency
 Peripheral interfaces
Baseband
PMIC
Transceiver
NAND
DDR2
SDRAM
PA
Switch
LNA
Switch
ANT_MAIN ANT_DIVANT_GNSS
VBAT_BB
VBAT_RF
APT
PWRKEY
ADCs
VDD_EXT
USB
USIM
PCM
UART
I2C
RESET_N
19.2M
XO
STATUS
GPIOs
SAW
Control
IQ Control
Duplex
SAW
Tx
PRx DRx
SGMII
WLAN
BT
Figure 1: Functional Diagram
2.4. Evaluation Board
In order to help youdevelop applications with EC21, Quectel supplies an evaluation board (EVB), USB
data cable, earphone, antenna and other peripherals to control or test the module.