Bit microcontroller with infrared module maxq613 – Rainbow Electronics MAXQ613 User Manual
Page 26
16-Bit Microcontroller with Infrared Module
MAXQ613
26 _____________________________________________________________________________________
Figure 13. Stop Mode Power-Fail Detection with Power-Fail Monitor Disabled
Table 6. Stop Mode Power-Fail Detection States with Power-Fail Monitor Disabled
V
PFW
V
RST
V
POR
V
DD
A
B
C
D
E
F
STOP
INTERRUPT
INTERNAL RESET
(ACTIVE HIGH)
STATE
POWER-FAIL
INTERNAL
REGULATOR
CRYSTAL
OSCILLATOR
SRAM
RETENTION
COMMENTS
A
Off
Off
Off
Yes
Application enters stop mode.
V
DD
> V
RST
.
CPU in stop mode.
B
Off
Off
Off
Yes
V
DD
< V
PFW
.
Power-fail not detected because power-fail
monitor is disabled.
C
On
On
On
Yes
V
RST
< V
DD
< V
PFW
.
An interrupt occurs that causes the CPU to
exit stop mode.
Power-fail monitor is turned on, detects a
power-fail warning, and sets the power-fail
interrupt flag.
Turn on regulator and crystal.
Crystal warmup time, t
XTAL_RDY
.
On stop mode exit, CPU vectors to the
higher priority of power-fail and the inter-
rupt that causes stop mode exit.