ATAM893X-TKHYZ ATMEL [ATMEL Corporation], ATAM893X-TKHYZ Datasheet - Page 13

• Manufacturer Part Number: ATAM893X-TKHYZ
• Description: Flash Version for ATAR080, ATAR090/890 and ATAR092/892
• Manufacturer: ATMEL [ATMEL Corporation]

4.3.2
4.3.3
4.4
4680C–4BMCU–01/05
Voltage Monitor
Watchdog Reset
External Clock Supervisor
Figure 4-8.
The watchdog's function can be enabled at the WDC register and triggers a reset with every
watchdog counter overflow. To suppress the watchdog reset, the watchdog counter must be
regularly reset by reading the watchdog register address (CWD). The CPU reacts in exactly the
same manner as a reset stimulus from any of the above sources.
The external input clock supervisor function can be enabled if the external input clock is selected
within the CM and SC registers of the clock module. The CPU reacts in exactly the same man-
ner as a reset stimulus from any of the above sources.
The voltage monitor consists of a comparator with an internal voltage reference. It is used to
supervise the supply voltage or an external voltage at the VMI pin. The comparator for the sup-
ply voltage has three internal programmable thresholds: one lower threshold (2.2 V), one middle
threshold (2.6 V) and one higher threshold (3.0 V). For external voltages at the VMI pin, the
comparator threshold is set to V
below (VMS = 0) or above (VMS = 1) this threshold. An interrupt can be generated when the
VMS bit is set or reset to detect a rising or falling slope. A voltage monitor interrupt (INT7) is
enabled when the interrupt mask bit (VIM) is reset in the VMC register.
Reset
Reset
CPU
CPU
2.0 V
1.7 V
V
BOT = 1, low brown-out voltage threshold 1.7 V (is reset value).
BOT = 0, high brown-out voltage threshold 2.0 V.
DD
Brown-out Detection
BOT = 1
BOT = 0
BG
t
= 1.3 V. The VMS bit indicates if the supervised voltage is
d
t
= 1.5 ms (typically)
d
t
d
ATAM893-D
t
d
t
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