MC68HC705P9CS datasheet(27/160 Pages) FREESCALE

27 / 160 page

Pin Descriptions

Pin Functions

MC68HC705P9 — Rev. 4.0

Technical Data

MOTOROLA

Pin Descriptions

2.3.2 OSC1 and OSC2

The OSC1 and OSC2 pins are the connections for the on-chip oscillator.

The oscillator can be driven by any of the following:

•

Crystal

•

Ceramic resonator

•

External clock signal

The frequency of the on-chip oscillator is f

OSC. The MCU divides the

internal oscillator output by two to produce the internal clock with a

frequency of f

OP.

2.3.2.1 Crystal Connections

The circuit in Figure 2-3 shows a

typical crystal oscillator circuit

for an AT-cut, parallel resonant

crystal. Follow the crystal

supplier’s recommendations, as

the crystal parameters

determine the external

component values required to

provide reliable startup and

maximum stability. The load

capacitance values used in the

oscillator circuit design should

include all stray layout

capacitances. To minimize

output distortion, mount the

crystal and capacitors as close

as possible to the pins.

NOTE:

Use an AT-cut crystal. Do not use a strip or tuning fork crystal. The MCU

may overdrive or have the incorrect characteristic impedance for a strip

or tuning fork crystal.

MCU

XTAL

10 M

Ω

27 pF

Figure 2-3. Crystal Connections

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

MC68HC705P9CS 数据表(PDF) 27 Page - Freescale Semiconductor, Inc

MC68HC705P9CS 数据表(HTML) 27 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载