
PIC18F1230/1330
DS39758D-page 286
2009 Microchip Technology Inc.
23.4.3
TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 23-6:
EXTERNAL CLOCK TIMING (ALL MODES EXCEPT PLL)
TABLE 23-6:
EXTERNAL CLOCK TIMING REQUIREMENTS
Param.
No.
Symbol
Characteristic
Min
Max
Units
Conditions
1A
FOSC
External CLKI Frequency(1)
DC
1
MHz
XT, RC Oscillator modes
DC
40
MHz
EC Oscillator mode
DC
31.25
kHz
LP Oscillator mode
Oscillator Frequency(1)
DC
4
MHz
RC Oscillator mode
0.1
4
MHz
XT Oscillator mode
4
20
MHz
HS Oscillator mode
5
200
kHz
LP Oscillator mode
1TOSC
External CLKI Period(1)
1000
—
ns
XT, RC Oscillator modes
50
—
ns
HS Oscillator mode
25
—
ns
EC Oscillator mode
Oscillator Period(1)
250
—
ns
RC Oscillator mode
250
1
s
XT Oscillator mode
50
250
ns
HS Oscillator mode
100
250
ns
HS +PLL Oscillator mode
5200
s
LP Oscillator mode
2TCY
Instruction Cycle Time(1)
100
—
ns
TCY = 4/FOSC, Industrial
160
—
ns
TCY = 4/FOSC, Extended
3TOSL,
TOSH
External Clock in (OSC1)
High or Low Time
30
—
ns
XT Oscillator mode
2.5
—
s
LP Oscillator mode
10
—
ns
HS Oscillator mode
4TOSR,
TOSF
External Clock in (OSC1)
Rise or Fall Time
—
20
ns
XT Oscillator mode
—
50
ns
LP Oscillator mode
—
7.5
ns
HS Oscillator mode
Note 1:
Instruction cycle period (TCY) equals four times the input oscillator time base period for all configurations
except PLL. All specified values are based on characterization data for that particular oscillator type under
standard operating conditions with the device executing code. Exceeding these specified limits may result
in an unstable oscillator operation and/or higher than expected current consumption. All devices are tested
to operate at “min.” values with an external clock applied to the OSC1/CLKI pin. When an external clock
input is used, the “max.” cycle time limit is “DC” (no clock) for all devices.
OSC1
CLKO
Q4
Q1
Q2
Q3
Q4
Q1
1
2
33
4