MC68HC705C8A_13 Datasheet, PDF (182/222 Pages) Freescale Semiconductor, Inc – Technical Data

Freescale Semiconductor, Inc.
Electrical Specifications
13.10 3.3-Volt Control Timing
Characteristic⁽¹⁾
Frequency of operation
Crystal option
External clock option
Symbol
Min
f_OSC
—
dc
Max
Unit
2.0
2.0
MHz
Internal operating frequency
Crystal (f_OSC ÷ 2)
External clock (f_OSC ÷ 2)
Cycle time (see Figure 13-7)
Crystal oscillator startup time (see Figure 13-7)
Stop recovery startup time (crystal oscillator)
(see Figure 13-6)
f_OP
—
dc
1.0
1.0
MHz
t_CYC
1000
—
ns
t_OXOV
—
100
ms
t_ILCH
—
100
ms
RESET pulse width, excluding power-up
(see Figure 13-7)
t_RL
8
—
t_CYC
Timer
Resolution⁽²⁾
Input capture pulse width (see Figure 13-5)
Input capture pulse period (see Figure 13-5)
Interrupt pulse width low (edge-triggered)
(see Figure 4-2. External Interrupt Timing)
t_RESL
4.0
t_TH, t_TL
250
t_TLTL
(3)
t_ILIH
250
—
t_CYC
—
ns
—
t_CYC
—
ns
Interrupt pulse period
(see Figure 4-2. External Interrupt Timing)
t_ILIL
(4)
—
t_CYC
OSC1 pulse width
t_OH, t_OL
200
—
ns
1. V_DD = 3.3 Vdc ± 0.3 Vdc, V_SS = 0 Vdc; T_A = T_L to T_H
2. Since a 2-bit prescaler in the timer must count four internal cycles (t_CYC), this is the limiting minimum factor in determining
the timer resolution.
3. The minimum period, t_TLTL, should not be less than the number of cycle times it takes to execute the capture interrupt ser-
vice routine plus 24 t_CYC.
4. The minimum period, t_ILIL, should not be less than the number of cycle times it takes to execute the interrupt service routine
plus 19 t_CYC.
EXTERNAL SIGNAL
(TCAP PIN 37)
t_TLTL*
t_TH*
t_TL*
*_{Refer to timer resolution data in Figure 13-6 and Figure 13-7.}
Figure 13-5. Timer Relationships
Technical Data
182
Electrical Specifications
For More Information On This Product,
Go to: www.freescale.com
MC68HC705C8A — Rev. 3