Microchip Technology ARD00385 数据表
2009-2011 Microchip Technology Inc.
DS39957D-page 529
PIC18F87K90 FAMILY
TABLE 31-10: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
No.
Symbol
Characteristic
Min
Typ
Max
Units
Conditions
30
TmcL
MCLR Pulse Width (low)
2
—
—
s
V
DD
= 3.3-5.0V,
-40°C to +85°C
5
—
—
s
V
DD
= 3.3-5.0V
31
T
WDT
Watchdog Timer Time-out Period
(no postscaler)
(no postscaler)
—
4.00
—
ms
32
T
OST
Oscillation Start-up Timer Period
1024 T
OSC
—
1024 T
OSC
—
T
OSC
= OSC1 period
33
T
PWRT
Power-up Timer Period
—
65.5
140
ms
34
T
IOZ
I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
Low or Watchdog Timer Reset
—
2
—
s
35
T
BOR
Brown-out Reset Pulse Width
200
—
—
s
V
DD
B
VDD
(see
)
36
T
IRVST
Time for Internal Reference
Voltage to become Stable
Voltage to become Stable
—
25
—
s
37
T
HLVD
High/Low-Voltage Detect Pulse Width
200
—
—
s
V
DD
V
HLVD
38
T
CSD
CPU Start-up Time
5
—
10
s
39
T
IOBST
Time for INTOSC to Stabilize
—
1
—
s