User's Manual

LTE Module Series
EC25Hardware Design
EC25_Hardware_DesignConfidential / Released 8 / 90
Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM ............................................................................................................... 16
FIGURE 2: PIN ASSIGNMENT (TOP VIEW) .................................................................................................... 18
FIGURE 3: SLEEP MODE APPLICATION VIA UART ....................................................................................... 29
FIGURE 4: SLEEP MODE APPLICATION WITH USB REMOTE WAKEUP .................................................... 30
FIGURE 5: SLEEP MODE APPLICATION WITH RI ......................................................................................... 30
FIGURE 6: SLEEP MODE APPLICATION WITHOUT SUSPEND FUNCTION ................................................ 31
FIGURE 7: POWER SUPPLY LIMITS DURING BURST TRANSMISSION ...................................................... 33
FIGURE 8: STAR STRUCTURE OF THE POWER SUPPLY ............................................................................ 33
FIGURE 9: REFERENCE CIRCUIT OF POWER SUPPLY .............................................................................. 34
FIGURE 10: TURN ON THE MODULE USING DRIVING CIRCUIT ................................................................. 35
FIGURE 11: TURN ON THE MODULE USING KEYSTROKE .......................................................................... 35
FIGURE 12: TIMING OF TURNING ON MODULE ........................................................................................... 36
FIGURE 13: TIMING OF TURNING OFF MODULE ......................................................................................... 37
FIGURE 14: REFERENCE CIRCUIT OF RESET_N BY USING DRIVING CIRCUIT ...................................... 38
FIGURE 15: REFERENCE CIRCUIT OF RESET_N BY USING BUTTON ...................................................... 38
FIGURE 16: TIMING OF RESETTING MODULE ............................................................................................. 38
FIGURE 17: REFERENCE CIRCUIT OF USIM CARD INTERFACE WITH AN 8-PIN USIM CARD
CONNECTOR .................................................................................................................................................... 40

FIGURE 18: REFERENCE CIRCUIT OF USIM CARD INTERFACE WITH A 6-PIN USIM CARD CONNECTOR
........................................................................................................................................................................... 40

FIGURE 19: REFERENCE CIRCUIT OF USB APPLICATION ......................................................................... 42
FIGURE 20: REFERENCE CIRCUIT WITH TRANSLATOR CHIP ................................................................... 44
FIGURE 21: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT .............................................................. 45
FIGURE 22: PRIMARY MODE TIMING ............................................................................................................ 46
FIGURE 23: AUXILIARY MODE TIMING .......................................................................................................... 46
FIGURE 24: REFERENCE CIRCUIT OF PCM APPLICATION WITH AUDIO CODEC .................................... 47
FIGURE 25: REFERENCE CIRCUIT OF THE NETWORK INDICATOR .......................................................... 49
FIGURE 26: REFERENCE CIRCUITS OF STATUS ......................................................................................... 50
FIGURE 27: SIMPLIFIED BLOCK DIAGRAM FOR ETHERNET APPLICATION ............................................. 52
FIGURE 28: REFERENCE CIRCUIT OF SGMII INTERFACE WITH PHY AR8033 APPLICATION ................. 52
FIGURE 29: REFERENCE CIRCUIT OF WIRELESS CONNECTIVITY INTERFACES WITH FC20 MODULE
........................................................................................................................................................................... 55

FIGURE 30: REFERENCE CIRCUIT OF USB_BOOT INTERFACE ................................................................ 57
FIGURE 31: REFERENCE CIRCUIT OF RF ANTENNA INTERFACE ............................................................. 61
FIGURE 32: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB ...................................................................... 62
FIGURE 33: COPLANAR WAVEGUIDE LINE DESIGN ON A 2-LAYER PCB .................................................. 62
FIGURE 34: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND) .......................................................................................................................................................... 63

FIGURE 35: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND) .......................................................................................................................................................... 63

FIGURE 36: REFERENCE CIRCUIT OF GNSS ANTENNA ............................................................................. 64