Figure 11: Turn On The Module Using Keystroke - Quectel EC21 Series Hardware Design

The turn on scenario is illustrated in the following figure.
VBAT
PWRKEY
RESET_N
STATUS
(OD)
UART
USB
NOTE
Please make sure that VBAT is stable before pulling down PWRKEY pin. The time between them is no
less than 30ms.
EC21_Hardware_Design
S1
TVS
Close to S1

Figure 11: Turn on the Module Using Keystroke

NOTE
≥100ms
≤0.5V
V
IL
≥2.5s
Inactive
Inactive
Figure 12: Timing of Turning on Module
Confidential / Released
PWRKEY
≥1.3V
V
IH
≥12s
≥13s
LTE Module Series
EC21 Hardware Design
Active
Active
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