MC68HC705KJ1 Datasheet, PDF (101/108 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Appendix A
MC68HRC705KJ1
A.1 Introduction
This appendix introduces the MC68HRC705KJ1, a resistor-capacitor (RC) oscillator mask option version
of the MC68HC705KJ1. All of the information in MC68HC705KJ1 Technical Data applies to the
MC68HRC705KJ1 with the exceptions given in this appendix.
A.2 RC Oscillator Connections
For greater cost reduction, the RC oscillator mask option allows the configuration shown in Figure A-1 to
drive the on-chip oscillator. Mount the RC components as close as possible to the pins for startup
stabilization and to minimize output distortion.
OSC1
R
OSC2
MCU
R
V_DD
C2 C1
V_SS
Figure A-1. RC Oscillator Connections
NOTE
The optional internal resistor is not recommended for configurations that
use the RC oscillator connections as shown in Figure A-1. For such
configurations, the oscillator internal resistor (OSCRES) bit of the mask
option register should be programmed to a logic 0.
MC68HC705KJ1 • MC68HRC705KJ1 • MC68HLC705KJ1 Data Sheet, Rev. 4.1
Freescale Semiconductor
101