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LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design Confidential / Released 36 / 94
PWRKEY
S1
Close to S1
TVS
Figure 11: Turn on the Module Using Keystroke
The turn on scenario is illustrated in the following figure.
V
IL
≤0.5V
V
IH
≥1.3V
VBAT
PWRKEY
≥100ms
RESET_N
STATUS
(OD)
Inactive
Active
UART
NOTE
Inactive
Active
USB
≥2.5s
≥12s
≥13s
Figure 12: Timing of Turning on Module
Please make sure that VBAT is stable before pulling down PWRKEY pin. The time between them is no
less than 30ms.
NOTE
Quectel
Confidential