PIC17C4X Datasheet, PDF (155/240 Pages) Microchip Technology – High-Performance 8-Bit CMOS EPROM/ROM Microcontroller

PIC17C4X
17.4 Timing Diagrams and Specifications
FIGURE 17-2: EXTERNAL CLOCK TIMING
Applicable Devices 42 R42 42A 43 R43 44
Q4
OSC1
OSC2 †
Q1
Q2
Q3
Q4
Q1
1
3
3
4
4
2
† In EC and RC modes only.
TABLE 17-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Parameter
No.
Sym
Characteristic
Min Typ† Max Units
Conditions
1
2
3
4
†
‡
Note 1:
Fosc External CLKIN Frequency
(Note 1)
DC
—
DC
—
16
MHz EC osc mode - PIC17C42-16
25
MHz
- PIC17C42-25
Oscillator Frequency
(Note 1)
DC
—
1
—
1
—
DC
—
4
MHz RC osc mode
16
MHz XT osc mode - PIC17C42-16
25
MHz
- PIC17C42-25
2
MHz LF osc mode
Tosc External CLKIN Period
(Note 1)
62.5 —
40
—
—
ns EC osc mode - PIC17C42-16
—
ns
- PIC17C42-25
Oscillator Period
(Note 1)
250 —
62.5 —
40
—
500 —
—
1,000
1,000
—
ns RC osc mode
ns XT osc mode - PIC17C42-16
ns
- PIC17C42-25
ns LF osc mode
TCY Instruction Cycle Time (Note 1)
160 4/Fosc DC
ns
TosL, Clock in (OSC1) High or Low Time 10 ‡ —
TosH
—
ns EC oscillator
TosR, Clock in (OSC1) Rise or Fall Time —
—
TosF
5‡
ns EC oscillator
Data in “Typ” column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only and are not
tested.
These parameters are for design guidance only and are not tested, nor characterized.
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 unstable oscillator operation and/or higher than expected current consump-
tion. All devices are tested to operate at “min.” values with an external clock applied to the OSC1 pin.
When an external clock input is used, the “Max.” cycle time limit is “DC” (no clock) for all devices.
© 1996 Microchip Technology Inc.
DS30412C-page 155