Datasheet

MC9S08QE32 Series MCU Data Sheet, Rev. 7
Electrical Characteristics
Freescale Semiconductor20
3.10 AC Characteristics
This section describes timing characteristics for each peripheral system.
3.10.1 Control Timing
8C
Total deviation of trimmed DCO output frequency over voltage
and temperature
f
dco_t
—
0.5
–1.0
2
%f
dco
9C
Total deviation of trimmed DCO output frequency over fixed
voltage and temperature range of 0
C to 70 C
f
dco_t
— 0.5 1
%f
dco
10 C
FLL acquisition time
3
t
Acquire
—— 1ms
11 C
Long term jitter of DCO output clock (averaged over 2-ms
interval)
4
C
Jitter
— 0.02 0.2
%f
dco
1
Data in Typical column is characterized at 3.0 V, 25 C or is typical recommended value.
2
The resulting bus clock frequency must not exceed the maximum specified bus clock frequency of the device.
3
This specification applies to any time the FLL reference source or reference divider is changed, trim value changed or
changing from FLL disabled (FBELP, FBILP) to FLL enabled (FEI, FEE, FBE, FBI). If a crystal/resonator is being used as
the reference, this specification assumes it is already running.
4
Jitter is the average deviation from the programmed frequency measured over the specified interval at maximum f
Bus
.
Measurements are made with the device powered by filtered supplies and clocked by a stable external clock signal. Noise
injected into the FLL circuitry via V
DD
and V
SS
and variation in crystal oscillator frequency increase the C
Jitter
percentage
for a given interval.
Table 12. Control Timing
Num C Rating Symbol Min Typical
1
Max Unit
1D
Bus frequency (t
cyc
= 1/f
Bus
)
V
DD
 2.1V
2.1<V
DD
 2.4V
V
DD
> 2.4Vs
f
Bus
DC —
10
20
25.165
MHz
2 D Internal low power oscillator period
t
LPO
700 — 1300 s
3D
External reset pulse width
2
t
extrst
100 — — ns
4 D Reset low drive
t
rstdrv
34  t
cyc
——ns
5D
BKGD/MS setup time after issuing background debug
force reset to enter user or BDM modes
t
MSSU
500 — — ns
6D
BKGD/MS hold time after issuing background debug
force reset to enter user or BDM modes
3
t
MSH
100 — — s
7D
IRQ pulse width
Asynchronous path
2
Synchronous path
4
t
ILIH,
t
IHIL
100
1.5  t
cyc
—
—
—
—
ns
Table 11. ICS Frequency Specifications (Temperature Range = –40 to 85C Ambient) (continued)
Num C Characteristic Symbol Min Typical
1
Max Unit