Datasheet

Table Of Contents
PIC18F85J90 FAMILY
DS39770C-page 376 2010 Microchip Technology Inc.
26.4.3 TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 26-4: EXTERNAL CLOCK TIMING
TABLE 26-7: EXTERNAL CLOCK TIMING REQUIREMENTS
Param.
No.
Symbol Characteristic Min Max Units Conditions
1A F
OSC External CLKI Frequency
(1)
DC 40 MHz ECPLL Oscillator mode
Oscillator Frequency
(1)
DC 40 MHz HSPLL Oscillator mode
1TOSC External CLKI Period
(1)
25 ns EC Oscillator mode
Oscillator Period
(1)
25 250 ns HS Oscillator mode
2T
CY Instruction Cycle Time
(1)
100 ns TCY = 4/FOSC, Industrial
3TOSL,
T
OSH
External Clock in (OSC1)
High or Low Time
10 ns EC Oscillator mode
4T
OSR,
T
OSF
External Clock in (OSC1)
Rise or Fall Time
7.5 ns EC 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
3
3
4
4