Datasheet

AC Characteristics
MC9S08SF4 Series MCU Data Sheet, Rev. 4
Freescale Semiconductor 19
3.9.2 Timer/PWM (TPM) Module Timing
Synchronizer circuits determine the shortest input pulses that can be recognized or the fastest clock that
can be used as the optional external source to the timer counter. These synchronizers operate from the
current bus rate clock.
Figure 16. Timer External Clock
Figure 17. Timer Input Capture Pulse
Table 10. TPM/MTIM Input Timing
Function Symbol Min Max Unit
External clock frequency f
TCLK
dc f
timer
/4 MHz
External clock period t
TCLK
4—t
cyc
External clock high time t
clkh
1.5 — t
cyc
External clock low time t
clkl
1.5 — t
cyc
Input capture pulse width for TPM t
ICPW
1.5 — t
cyc
Timer clock frequency f
timer
—40MHz
t
Text
t
clkh
t
clkl
TCLK
t
ICPW
TPMCHn
t
ICPW
TPMCHn