PIC17C44 Datasheet, PDF (184/241 Pages) Microchip Technology – High-Performance 8-Bit CMOS EPROM/ROM Microcontroller

PIC17C4X
Applicable Devices 42 R42 42A 43 R43 44
19.5 Timing Diagrams and Specifications
FIGURE 19-2: EXTERNAL CLOCK TIMING
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
2
3
4
4
OSC2 †
† In EC and RC modes only.
TABLE 19-2: EXTERNAL CLOCK TIMING REQUIREMENTS
Param
No. Sym
Characteristic
Min Typ† Max Units
Conditions
1
2
3
4
†
‡
Note 1:
Fosc External CLKIN Frequency ^DC
—
(Note 1)
DC
—
DC
—
DC
—
8 MHz EC osc mode - 08 devices (8 MHz devices)
16 MHz
- 16 devices (16 MHz devices)
25 MHz
- 25 devices (25 MHz devices)
33 MHz
- 33 devices (33 MHz devices)
Oscillator Frequency
(Note 1)
DC
—
1
—
1
—
1
—
1
—
DC
—
4 MHz RC osc mode
8 MHz XT osc mode - 08 devices (8 MHz devices)
16 MHz
- 16 devices (16 MHz devices)
25 MHz
- 25 devices (25 MHz devices)
33 MHz
- 33 devices (33 MHz devices)
2 MHz LF osc mode
Tosc External CLKIN Period
(Note 1)
125 —
62.5 —
40
—
30.3 —
—
ns EC osc mode - 08 devices (8 MHz devices)
—
ns
- 16 devices (16 MHz devices)
—
ns
- 25 devices (25 MHz devices)
—
ns
- 33 devices (33 MHz devices)
Oscillator Period
(Note 1)
250 —
—
ns RC osc mode
125 — 1,000 ns XT osc mode - 08 devices (8 MHz devices)
62.5 — 1,000 ns
- 16 devices (16 MHz devices)
40
— 1,000 ns
- 25 devices (25 MHz devices)
30.3 — 1,000 ns
- 33 devices (33 MHz devices)
500 —
—
ns LF osc mode
TCY Instruction Cycle Time
(Note 1)
121.2 4/Fosc DC ns
TosL, Clock in (OSC1)
TosH high or low time
10 ‡ —
—
ns EC oscillator
TosR, Clock in (OSC1)
TosF rise or fall time
—
—
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 an unstable oscillator operation and/or higher than expected current con-
sumption. All devices are tested to operate at “min.” values with an external clock applied to the OSC1/CLKIN pin.
When an external clock input is used, the “max.” cycle time limit is “DC” (no clock) for all devices.
DS30412C-page 184
© 1996 Microchip Technology Inc.