MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 209

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

13.4.4 MC68HC912Dx128C DC Blocking Capacitor Guidelines
MC68HC912DT128A — Rev 4.0
MOTOROLA
Due to the placement of the resonator from EXTAL to VSS and the
nature of the microcontroller’s inputs, there will be a DC bias voltage of
approximately (VDD–2V) across the pins of the resonator. For some
resonators, this can have long-term reliability issues. To remedy this
situation, a DC-blocking capacitor can be placed in series with the
crystal, as shown in
The value of the DC-blocking capacitor should be between 0.1 and
10nF, with a preferred value of 1nF. This capacitor must be connected
as shown in
specifications and guidelines continue to apply.
Figure
13-3. If connected thus, all other oscillator
Oscillator
Figure
MC68HC912Dx128C Colpitts Oscillator Specification
13-3.
Technical Data
Oscillator
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