attiny167-esxz ATMEL Corporation, attiny167-esxz Datasheet - Page 49

• Manufacturer Part Number: attiny167-esxz
• Description: 8-bit Avr 8-bit Microcontroller Microcontroller With 16k Bytes In-system Programmable Flash And Lin Controller
• Manufacturer: ATMEL Corporation

6.1.4
6.1.5
7728A–AUTO–07/08
External Reset
Brown-out Detection
Figure 6-3.
An External Reset is generated by a low level on the RESET pin. Reset pulses longer than the
minimum pulse width (see
running. Shorter pulses are not guaranteed to generate a reset. When the applied signal
reaches the Reset Threshold Voltage – V
MCU after the Time-out period – t
RSTDISBL fuse, see
Figure 6-4.
ATtiny167 has an On-chip Brown-out Detection (BOD) circuit for monitoring the Vcc level during
operation by comparing it to a fixed trigger level. The trigger level for the BOD can be selected
by the BODLEVEL Fuses
a hysteresis to ensure spike free Brown-out Detection. The hysteresis on the detection level
should be interpreted as V
When the BOD is enabled, and Vcc decreases to a value below the trigger level (V
6-5), the Brown-out Reset is immediately activated. When Vcc increases above the trigger level
(V
expired.
The BOD circuit will only detect a drop in Vcc if the voltage stays below the trigger level for
longer than t
BOT
+
INTERNAL
TIME-OUT
in
RESET
RESET
Figure
V
CC
CC
BOD
MCU Start-up, RESET Extended Externally
External Reset During Operation
given in
6-5), the delay counter starts the MCU after the Time-out period t
Table 21-4 on page
Table 22-6 on page
V
CCRR
(See ”BODLEVEL Fuse Coding” on page
BOT
Table 22-3 on page
+
= V
TOUT
BOT
V
POR
– has expired. The External Reset can be disabled by the
+ V
RST
217.
HYST
237.
– on its positive edge, the delay counter starts the
236) will generate a reset, even if the clock is not
/ 2 and V
BOT
V
RST
–
= V
t
TOUT
BOT
- V
237.). The trigger level has
HYST
/ 2.
ATtiny167
BOT
–
TOUT
in
Figure
has
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