HC05RC16GRSSLASHD datasheet(24/122 Pages) NXP

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General Description

General Release Specification

MC68HC05RC16 — Rev. 3.0

General Description

1.5.3 OSC1 and OSC2

These pins provide control input for an on-chip clock oscillator circuit. A

crystal, a ceramic resonator, or an external signal connects to these pins

to provide a system clock. The oscillator frequency is two times the

internal bus rate.

Figure 1-5 shows the recommended circuit when using a crystal. The

crystal and components should be mounted as close as possible to the

input pins to minimize output distortion and startup stabilization time.

A ceramic resonator may be used in place of the crystal in cost-sensitive

applications. Figure 1-5 (a) shows the recommended circuit for using a

ceramic resonator. The manufacturer of the particular ceramic resonator

being considered should be consulted for specific information.

An external clock should be applied to the OSC1 input with the OSC2 pin

not connected (see Figure 1-5 (b)). This setup can be used if the user

does not want to run the CPU with a crystal.

Figure 1-5. Oscillator Connections

OSC1

OSC2

OSC1

OSC2

MCU

EXTERNAL CLOCK

UNCONNECTED

(a) Crystal/Ceramic Resonator

(b) External Clock Source

10 M

Ω

Oscillator Connections

Connections

30 pF

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

HC05RC16GRS/D Datasheet(PDF) 24 Page - NXP Semiconductors