PIC18F6520-I Datasheet, PDF (324/380 Pages) Micrel Semiconductor – 64/80-Pin High-Performance, 256 Kbit to 1 Mbit Enhanced Flash Microcontrollers with A/D

PIC18F6520/8520/6620/8620/6720/8720
26.4.3 TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 26-7:
EXTERNAL CLOCK TIMING (ALL MODES EXCEPT PLL)
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
CLKO
1
3
3
4
4
2
TABLE 26-6: EXTERNAL CLOCK TIMING REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Max
Units
Conditions
1A
FOSC
External CLKI Frequency⁽¹⁾
DC
25
MHz EC, ECIO, PIC18FX620/X720
(-40°C to +85°C)
DC
40
MHz EC, ECIO, PIC18FX520 (-40°C to +85°C)
Oscillator Frequency⁽¹⁾
DC
25
MHz EC, ECIO, PIC18FX520 using external
memory interface (-40°C to +85°C)
DC
4
MHz RC oscillator
0.1
4
MHz XT oscillator
4
25
MHz HS oscillator
4
10
MHz HS + PLL oscillator, PIC18FX520
4
6.25
MHz HS + PLL oscillator, PIC18FX520 using
external memory interface
4
6.25
MHz HS + PLL oscillator, PIC18FX620/X720
5
33
kHz LP Oscillator mode
1
TOSC
External CLKI Period⁽¹⁾
40
—
ns EC, ECIO, PIC18FX620/X720
(-40°C to +85°C)
Oscillator Period⁽¹⁾
25
—
ns ^{EC, ECIO, PIC18FX520 (-40°C to +85°C)}
40
—
ns ^{EC, ECIO, PIC18FX520 using external}
memory interface (-40°C to +85°C)
250
—
ns RC oscillator
250
10,000
ns XT oscillator
40
250
ns HS oscillator
100
250
ns HS + PLL oscillator, PIC18FX520
160
250
ns HS + PLL oscillator, PIC18FX620/X720
30
200
µs LP oscillator
2
TCY
Instruction Cycle Time⁽¹⁾
100
—
ns
TCY = 4/FOSC
3
TOSL,
External Clock in (OSC1)
30
TOSH
High or Low Time
2.5
—
ns XT oscillator
—
µs LP oscillator
10
—
ns HS oscillator
4
TOSR,
External Clock in (OSC1)
—
TOSF
Rise or Fall Time
—
20
ns XT oscillator
50
ns LP oscillator
—
7.5
ns HS oscillator
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.
DS39609B-page 322
 2004 Microchip Technology Inc.