CXD2931R-9/GA-9
CXD2931R-9/GA-9 Initialization
CXD2931R-9/GA-9 initialization is started by setting the reset input signal EXRS (Pin 27) to low level. The
timing should satisfy the conditions noted below.
1. During power-on (power-on reset) (VDD = 3.0 to 3.6V, Topr = –40 to +85°C)
VDD
VDD [V]
Power supply,
PWRST
(Pin 28)
100ms or more
EXRS (Pin 27)
VDD/2
GND
The PWRST (Pin 28) signal should rise simultaneously with the power supply. The EXRS (Pin 27) signal
should rise 100ms or more after the power supply and the PWRST signal have risen. Note that the PWRST
signal should be left open during battery backup.
2. Initialization during operation (VDD = 3.0 to 3.6V, Topr = –40 to +85°C)
VDD
VDD [V]
Power supply,
PWRST
(Pin 28)
100µs or more
EXRS (Pin 27)
VDD/2
GND
The internal registers can be initialized during operation by setting the EXRS (Pin 27) signal to low level for
100µs or more. Keep the PWRST (Pin 28) signal at high level at this time.
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