GMS82524 Datasheet, PDF (62/93 Pages) Hynix Semiconductor – 8-BIT SINGLE-CHIP MICROCONTROLLERS

HYUNDAI MicroElectronics
GMS82512/16/24
17. OSCILLATOR CIRCUIT
The GMS825xx has two oscillation circuits internally. X_IN
and X_OUT are input and output for frequency, respectively,
inverting amplifier which can be configured for being used
as an on-chip oscillator, as shown in Figure 17-1.
C1
X_OUT
C2
8MHz
X_IN
V_SS
Recommend
Crystal Oscillator
C1,C2 = 30pF±10pF
Crystal or Ceramic Oscillator
Open
External Clock
X_OUT
X_IN
External Oscillator
Figure 17-1 Oscillation Circuit
Oscillation circuit is designed to be used either with a ce-
ramic resonator or crystal oscillator. Since each crystal and
ceramic resonator have their own characteristics, the user
should consult the crystal manufacturer for appropriate
values of external components.
Oscillation circuit is designed to be used either with a ce-
ramic resonator or crystal oscillator. Since each crystal and
ceramic resonator have their own characteristics, the user
X_OUT
should consult the crystal manufacturer for appropriate
values of external components.
X_IN
In addition, see Figure 17-2 for the layout of the crystal.
Note: Minimize the wiring length. Do not allow the wiring to
intersect with other signal conductors. Do not allow the wir-
ing to come near changing high current. Set the potential of
the grounding position of the oscillator capacitor to that of
VSS. Do not ground it to any ground pattern where high cur-
rent is present. Do not fetch signals from the oscillator.
Figure 17-2 Layout of Oscillator PCB circuit
FEB. 2000 Ver 1.00
59