English
Language : 

PIC18LF24K Datasheet, PDF (545/594 Pages) –
PIC18(L)F26/45/46K40
FIGURE 37-5:
CLOCK TIMING
Q4
Q1
CLKIN
OS1
CLKOUT
(CLKOUT Mode)
Note 1: See Table 37-7.
Q2
Q3
OS2
OS20
Q4
Q1
OS2
TABLE 37-7: EXTERNAL CLOCK/OSCILLATOR TIMING REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Param
No.
Sym.
ECL Oscillator
Characteristic
Min. Typ† Max. Units
Conditions
OS1
FECL
Clock Frequency
—
—
500
kHz
OS2
TECL_DC Clock Duty Cycle
40
—
60
%
ECM Oscillator
OS3
FECM
Clock Frequency
—
—
4
MHz
OS4
TECM_DC Clock Duty Cycle
40
—
60
%
ECH Oscillator
OS5
FECH
Clock Frequency
—
—
32
MHz
OS6
TECH_DC Clock Duty Cycle
40
—
60
%
LP Oscillator
OS7
FLP
Clock Frequency
—
—
100
kHz Note 4
XT Oscillator
OS8
FXT
Clock Frequency
—
—
4
MHz Note 4
HS Oscillator
OS9
FHS
Clock Frequency
—
—
20
MHz Note 4
Secondary Oscillator
OS10 FSEC
Clock Frequency
32.4 32.768 33.1
kHz
System Oscillator
OS20 FOSC
System Clock Frequency
—
—
64
MHz (Note 2, Note 3)
* These parameters are characterized but not tested.
† Data in “Typ” column is at 3.0V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period. 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 OSC1 pin.
When an external clock input is used, the “max” cycle time limit is “DC” (no clock) for all devices.
2: The system clock frequency (FOSC) is selected by the “main clock switch controls” as described in Section 6.0 “Power-
Saving Operation Modes”.
3: The system clock frequency (FOSC) must meet the voltage requirements defined in the Section 37.2 “Standard
Operating Conditions”.
4: LP, XT and HS oscillator modes require an appropriate crystal or resonator to be connected to the device. For clocking
the device with the external square wave, one of the EC mode selections must be used.
 2016 Microchip Technology Inc.
Preliminary
DS40001816C-page 545