MC68HC908KX8 Datasheet, PDF (107/310 Pages) Motorola, Inc – Microcontrollers

Internal Clock Generator Module (ICG)
Functional Description
7.4.3 External Clock Generator
The ICG also provides for an external oscillator or external clock source,
if desired. The external clock generator, shown in Figure 7-3, contains
an external oscillator amplifier and an external clock input path.
ECGEN
EXTXTALEN
EXTSLOW
EXTERNAL
CLOCK
GENERATOR
INTERNAL TO MCU
EXTERNAL
INPUT PATH
AMPLIFIER
OSC1
PTB6
R_B
OSC2
PTB7
ECLK
NAME
NAME
NAME
NAME
CONFIGURATION (OR MOR) BIT
TOP LEVEL SIGNAL
REGISTER BIT
MODULE SIGNAL
R_S
X₁
*R_S can be 0 (shorted)
when used with higher-
frequency crystals. Refer
to manufacturer’s data.
C₁
C₂
These components are required
for external crystal use only.
Figure 7-3. External Clock Generator Block Diagram
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 — Rev. 1.0
MOTOROLA
Internal Clock Generator Module (ICG)
Technical Data
107