MC68HC908BD48 Datasheet, PDF (111/290 Pages) Freescale Semiconductor, Inc – Microcontrollers

Technical Data — MC68HC908BD48
Section 8. Oscillator (OSC)
8.1 Contents
8.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
8.3 Oscillator External Connections . . . . . . . . . . . . . . . . . . . . . . . 112
8.4 I/O Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
8.4.1 Crystal Amplifier Input Pin (OSC1). . . . . . . . . . . . . . . . . . . 113
8.4.2 Crystal Amplifier Output Pin (OSC2) . . . . . . . . . . . . . . . . . 113
8.4.3 Oscillator Enable Signal (SIMOSCEN). . . . . . . . . . . . . . . . 113
8.4.4 External Clock Source (OSCXCLK) . . . . . . . . . . . . . . . . . . 113
8.4.5 Oscillator Out (OSCOUT). . . . . . . . . . . . . . . . . . . . . . . . . . 113
8.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.5.1 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.5.2 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.6 Oscillator During Break Mode. . . . . . . . . . . . . . . . . . . . . . . . . 114
8.2 Introduction
The oscillator circuit is designed for use with crystals or ceramic
resonators. The oscillator circuit generates the crystal clock signal,
OSCXCLK, at the frequency of the crystal. This signal is divided by two
before being passed on to the SIM for bus clock generation. Figure 8-1
shows the structure of the oscillator. The oscillator requires various
external components.
MC68HC908BD48 — Rev. 1.0
MOTOROLA
Oscillator (OSC)
Technical Data
111