|
MC68HC11PH8 Datasheet, PDF (31/264 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit | |||
|
◁ |
EXTAL
18 pF
2
(a) Common crystal connections
(32 to 38.4 kHz crystal)
M68HC11
22 Mâ¦
crystal
XTAL
390 kâ¦
20 pF
(a) Common crystal connections
(500 to 2000 kHz crystal)
EXTAL
M68HC11
XTAL
10 Mâ¦
crystal
25 pF
25 pF
(b) External oscillator
connections
EXTAL
M68HC11
XTAL
External oscillator
NC
Note: capacitor values include all stray capacitance.
Note: all values of capacitance and resistance shown are approximate; exact values must be calculated knowing the crystal parameters
and the expected voltage and temperature ranges.
Figure 2-5 Oscillator connections (VDDSYN = 1, PLL enabled)
2.4
E clock output (E)
E is the output connection for the internally generated E clock. The signal from E is used as a
timing reference. The frequency of the E clock output is one quarter that of the input frequency at
the XTAL and EXTAL pins (except when the PLL is used as the clock source). When E clock output
is low, an internal process is taking place; when it is high, data is being accessed. All clocks,
including the E clock, are halted when the MCU is in STOP mode. The E clock output can be
turned off to reduce the effects of RFI (see Section 3.3.2.5).
MC68HC11PH8
PIN DESCRIPTIONS
TPG
MOTOROLA
2-5
|
▷ |