PIC18F2525_08 Datasheet, PDF (348/412 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology

PIC18F2525/2620/4525/4620
FIGURE 26-10: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
T1OSO/T13CKI
40
41
42
45
46
47
48
TMR0 or
TMR1
Note: Refer to Figure 26-5 for load conditions.
TABLE 26-11: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Max Units Conditions
40 Tt0H
T0CKI High Pulse Width No prescaler 0.5 TCY + 20 — ns
With prescaler
10
— ns
41 Tt0L
T0CKI Low Pulse Width
No prescaler 0.5 TCY + 20 —
ns
With prescaler
10
— ns
42 Tt0P
T0CKI Period
No prescaler
TCY + 10
— ns
With prescaler Greater of:
— ns N = prescale
20 ns or
value
(TCY + 40)/N
(1, 2, 4,..., 256)
45 Tt1H
T13CKI Synchronous, no prescaler
0.5 TCY + 20
—
ns
High Time _{Synchronous, PIC18FXXXX}
10
— ns
with prescaler _PIC18LFXXXX
25
—
ns VDD = 2.0V
Asynchronous PIC18FXXXX
30
— ns
PIC18LFXXXX
50
—
ns VDD = 2.0V
46 Tt1L
T13CKI Synchronous, no prescaler
0.5 TCY + 5
—
ns
Low Time _{Synchronous, PIC18FXXXX}
10
— ns
with prescaler _PIC18LFXXXX
25
—
ns VDD = 2.0V
Asynchronous PIC18FXXXX
30
— ns
PIC18LFXXXX
50
—
ns VDD = 2.0V
47 Tt1P
T13CKI
Input
Period
Synchronous
Greater of:
—
20 ns or
(TCY + 40)/N
ns N = prescale
value (1, 2, 4, 8)
Asynchronous
60
— ns
Ft1
T13CKI Oscillator Input Frequency Range
DC
50 kHz
48 Tcke2tmrI Delay from External T13CKI Clock Edge to
Timer Increment
2 TOSC
7 TOSC —
DS39626E-page 346
© 2008 Microchip Technology Inc.