
1996 Microchip Technology Inc.
DS30412C-page 187
PIC17C4X
Applicable Devices 42 R42 42A 43 R43 44
FIGURE 19-5: TIMER0 CLOCK TIMINGS
TABLE 19-5:
TIMER0 CLOCK REQUIREMENTS
FIGURE 19-6: TIMER1, TIMER2, AND TIMER3 CLOCK TIMINGS
TABLE 19-6:
TIMER1, TIMER2, AND TIMER3 CLOCK REQUIREMENTS
Parameter
No.
Sym Characteristic
Min
Typ Max Units Conditions
40
Tt0H T0CKI High Pulse Width
No Prescaler
0.5TCY + 20 §
—
ns
With Prescaler
10*
—
ns
41
Tt0L T0CKI Low Pulse Width
No Prescaler
0.5TCY + 20 §
—
ns
With Prescaler
10*
—
ns
42
Tt0P T0CKI Period
Greater of:
20 ns or Tcy + 40 §
N
—
ns
N = prescale value
(1, 2, 4, ..., 256)
*
These parameters are characterized but not tested.
Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specication ensured by design.
Parameter
No.
Sym
Characteristic
Min
Typ
Max
Units Conditions
45
Tt123H
TCLK12 and TCLK3 high time
0.5TCY + 20 §
—
ns
46
Tt123L
TCLK12 and TCLK3 low time
0.5TCY + 20 §
—
ns
47
Tt123P
TCLK12 and TCLK3 input period
TCY + 40 §
N
—
ns
N = prescale value
(1, 2, 4, 8)
48
TckE2tmrI Delay from selected External Clock Edge to
Timer increment
2TOSC §
6Tosc §
*
These parameters are characterized but not tested.
Data in “Typ” column is at 5V, 25
°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
§
This specication ensured by design.
RA1/T0CKI
40
41
42
TCLK12
45
46
or
TCLK3
TMRx
48
47