SATEL-TR4+
Integration Guide, Version 1.6
15
3
TIME PARAMETERS FOR STARTUP AND SHUTDOWN
SEQUENCES
The following table shows the recommend times for startup and shutdown sequences.
Parameter
Recom. Time
(*
Explanation
t
vccin-ena
>2 ms
VCC_IN must be high before ENA_MOD is high
t
enamod-io
>2 ms
ENA_MOD must be high before VCC_IO is high
t
enamod-cts
100 ms<t
enamod-cts
< 500 ms
CTS ready settling time
t
vccio-cts
>2 ms
VCC_IO must be high before CTS is ready
t
vccio-gpio
>2 ms
VCC_IO must be high before GPIO PINS are active
t
gpio-cts
>0 ms
GPIOS must be active before CTS is ready
t
enamod-gpio
>80 ms
Input pins must be low after ENA MOD is low
t
gpio-vccio
>0 ms
GPIOs must be low before VCC_IO is low
t
vccio-vccin
>0 ms
VCC_IO must be low before VCC is low
3.1
Startup sequence
The following diagram will describe the startup sequence.
VCC_IN
ENA_MOD
VCC_IO
GPIOx_INPUT
GPIOx_OUTPU T
CTS1_OUT
t
vccin-ena
t
enamod-io
t
enamod-cts
t
vccio-cts
t
vccio-gpio
t
gpio-cts
Figure 3.1 Startup sequence.