
MOTOROLA
I-4
MC68HC05B6
Rev. 4
HIGH SPEED OPERATION
15
I.3
Control timing for 5V operation
(1) For bus frequencies less than 2 MHz, the internal RC oscillator should be used when
programmng the EEPROM.
(2) Since a 2-bit prescaler in the timer must count four external cycles (t
CYC
), this is the limting
factor in determning the timer resolution.
(3) The mnimumperiod t
TLTL
should not be less than the number of cycle times it takes to
execute the capture interrupt service routine plus 24 t
CYC
.
(4) The mnimumperiod t
ILIL
should not be less than the number of cycle times it takes to
execute the interrupt service routine plus 21 t
CYC
.
(5) At a temperature of 85
°
C
(6) Refer to Reliability Monitor Report (current quarterly issue) for current failure rate
information.
(V
DD
= 5.0 Vdc
±
10%, V
SS
= 0 Vdc, T
A
= –40 to +85
°
C)
Characteristic
Frequency of operation
Crystal option
External clock option
Internal operating frequency (f
OSC
/2)
Crystal
External clock
Cycle time (see Figure 9-1)
Crystal oscillator start-up time (see Figure 9-1)
Stop recovery start-up time (crystal oscillator)
External RESET input pulse width
Power-on RESET output pulse width
4064 cycle
16 cycle
Watchdog RESET output pulse width
Watchdog time-out
EEPROMbyte erase time
0 to 70 (standard)
– 40 to 85 (extended)
EEPROMbyte programtime
(1)
0 to 70 (standard)
– 40 to 85 (extended)
Timer (see Figure I-1)
Resolution
(2)
Input capture pulse width
Input capture pulse period
Interrupt pulse width (edge-triggered)
Interrupt pulse period
OSC1 pulse width
Write/Erase endurance
(5)(6)
Data retention
(5)(6)
Symbol
Mn
Max
Unit
f
OSC
f
OSC
—
dc
8.0
8.0
MHz
MHz
f
OP
f
OP
t
CYC
t
OXOV
t
ILCH
t
RL
—
dc
250
—
4.0
4.0
—
100
100
—
MHz
MHz
ns
ms
ms
t
CYC
1.5
t
PORL
t
PORL
t
DOGL
t
DOG
4064
16
1.5
6144
—
—
—
t
CYC
t
CYC
t
CYC
t
CYC
7168
t
ERA
t
ERA
10
10
—
—
ms
ms
t
PROG
t
PROG
10
10
—
—
ms
ms
t
RESL
t
TH
, t
TL
t
TLTL
t
ILIH
t
ILIL
t
OH
, t
OL
—
—
4
125
—
(3)
125
—
(4)
90
—
—
—
—
—
—
t
CYC
ns
t
CYC
ns
t
CYC
ns
cycles
years
10000
10
TPG