Parts List/Tune Up Info

Table 39 Power-off sequencing
Symbols
Pin Name
Min
Typ
Max
Unit
TOFF
Power off low level pulse width
16
--
--
s
TSTATUS
Shutdown time (judged by the
Status Pin)
25
26
--
s
TUART
BOOT time (according to UART
judgement)
14
15
--
s
3.4 Reset sequence
L508 can reset the module by pulling down the RESET or PWRKEY pin. Refer to 4.22.1
for a description of restarting the module.
Table 40 electrical properties of reset key signals
3.5 Interface application
PWRKEY, EXTON1N and RESET circuit can refer to the following diagram of the design
circuit.
Another way to control the PWRKEY, RESET, EXTON1N pin, is to use a physical key
switch directly. Place a TVS near the button for ESD protection. The following is the
reference circuit:
Symbols
Pin Name
Min
Typ
Max
Unit
VIH
Reset pin input high level voltage
1.26
1.8
2.0
V
VIL
Reset pin input low level voltage
-0.3
0
0.54
V