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MC68HC908RK2 Datasheet, PDF (223/232 Pages) Motorola, Inc – Microcontroller Unit
Preliminary Electrical Specifications
Control Timing
16.9 Control Timing
Characteristic
Symbol
Min
Max
Unit
Bus operating frequency
VDD = 3.0 V ± 10%
VDD = 2.0 V ± 10%
RESET pulse width low
IRQ interrupt pulse width low (edge-triggered)
IRQ interrupt pulse period
fBUS
32k
4.0 M
Hz
32k
2.0 M
tRL
1.5
—
tcyc
tILHI
1.5
—
tcyc
tILIL
Note 4
—
tcyc
16-bit timer (Note 2)
Input capture pulse width (Note 3)
Input capture period
Input clock pulse width
tTH, tTL
2
—
tcyc
tTLTL
Note 4
—
tcyc
tTCH, tTCL (1/fOP) + 5
—
ns
Notes:
1. VDD = 1.8 V to 3.3 V, VSS = 0 Vdc, TA = –40°C to +85°C, unless otherwise noted
2. The 2-bit timer prescaler is the limiting factor in determining timer resolution.
3. Refer to Table 15-3. Mode, Edge, and Level Selection and supporting note.
4. The minimum period tTLTL or tILIL should not be less than the number of cycles it takes to execute the capture interrupt
service routine plus 2 tcyc.
16.10 Internal Oscillator Characteristics
Characteristic(1)
Internal oscillator base frequency without
trim(2) (3)
Symbol
fINTOSC
Min
230.4
Typ
307.2
Max
Unit
384.0
kHz
Internal oscillator base frequency with trim(2) fINTOSC(I)
(3)
291.8
307.2
322.6
kHz
Internal oscillator multiplier(4)
N
1
—
127
—
External clock option(5)
3 V ± 10%
2 V ± 10%
fEXTOSC
128 k
—
128 k
—
16
MHz
8
1. VDD = 1.8 V to 3.3 V, VSS = 0 Vdc, TA = –40°C to +85°C, unless otherwise noted
2. Internal oscillator is selectable through software for a maximum frequency,. Actual frequency will be multiplier (N) x base
frequency.
3. fBUS = (fINTOSC / 4) x (internal oscillator multiplier)
4. Multiplier must be chosen to limit the maximum bus frequency to the maximum listed in 16.9 Control Timing.
5. No more than 10% duty cycle deviation from 50%
MC68HC908RK2 — Rev. 4.0
MOTOROLA
Preliminary Electrical Specifications
Advance Information
223