Z87C33 Datasheet, PDF (36/72 Pages) Zilog, Inc. – CMOS Z8® MCU Consumer Controller Processor

Z87C33
CMOS Z8“ MCU Consumer Controller Processor
30
Reset
4 Clock
Filter
Clear
CLK
18 Clock RESET
Generator _RESET
WDT Select (WDTMR)
Clock Source Select (WDTMR)
XTAL
V_DD
V_LV
WD_WTWWDTW
M
U
Internal
X
RC OSC
V_LV Operating
+
Voltage Det.
-
From Stop Mode Recovery Source
Stop Delay Select (SMR)
WDT TAP SELECT
7ms POR 3.5ms 7ms 14ms 56ms
CK _{WDT/POR Counter Chain}
CLK
bbbmc
cbcbb
hhh
Intern
In^IRIt^Ee^Srn^ETal
RESET
Figure 14.Resets and Watch-Dog Timer Example
Voltage Comparator
Low-Voltage Protection. An onboard Voltage Comparator checks that V_CC is at the
required level to ensure correct operation of the device. RESET is globally driven
if V_CC is below the specified voltage (Low-Voltage Protection). The minimum oper-
ating voltage varies with the temperature and operating frequency, while the Low-
Voltage Protection (V_LV) varies with temperature only.
The Low-Voltage Protection trip voltage (V_LV) is less than 3V and more than 1.4V
under the following conditions.
At 25ºC, the device functions normally at or above 3.0V. Below 3.0V, the device
functions normally until the Low-Voltage Protection trip point (V_LV) is reached for
the temperatures and operating frequencies in Table 15. The device is guaranteed
to function normally at supply voltages above the Low-Voltage Protection trip
PS015601-1003