HC05V7GRSSLASHD datasheet(24/170 Pages) NXP

24 / 170 page

SECTION 1: GENERAL DESCRIPTION

Page 10

MC68HC05V7 Specification Rev. 1.0

1.5.7

OSC1, OSC2

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

to the oscillator inverter. The output (OSC2) will always reflect OSC1 inverted except when

the device is in STOP mode, which forces OSC2 high. The OSC1, and OSC2 pins can

accept the following sets of components:

1. A crystal as shown in Figure 1-7(a)

2. A ceramic resonator as shown in Figure 1-7(a)

3. An external clock signal as shown in Figure 1-7(b)

The frequency, fOSC, of the oscillator or external clock source is divided by two to produce

the internal operating frequency, fOP.

1.5.7.1

Crystal Oscillator

The circuit in Figure 1-7(a) shows a typical oscillator circuit for an AT-cut, parallel resonant

crystal. The crystal manufacturer’s recommendations should be followed, as the crystal

parameters determine the external component values required to provide maximum

stability and reliable start-up. The load capacitance values used in the oscillator circuit

design should include all stray capacitances. The crystal and components should be

mounted as close as possible to the pins for start-up stabilization and to minimize output

distortion and radiated emissions.

Figure 1-7:

Oscillator Connections

1.5.7.2

Ceramic Resonator Oscillator

In cost-sensitive applications, a ceramic resonator can be used in place of the crystal. The

circuit in Figure 1-7(a) is for a ceramic resonator. The resonator manufacturer’s

recommendations should be followed, as the resonator parameters determine the external

component values required for maximum stability and reliable starting. The load

capacitance values used in the oscillator circuit design should include all stray

capacitances. The ceramic resonator and components should be mounted as close as

possible to the pins for start-up stabilization and to minimize output distortion and radiated

emissions.

MCU

(a) Crystal or

Ceramic Resonator

Connections

OSC1

OSC2

unconnected

External Clock

(b)External

Clock Source

Connection

OSC1

OSC2

MCU

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

HC05V7GRS/D Scheda tecnica(PDF) 24 Page - NXP Semiconductors

HC05V7GRS/D Scheda tecnica(HTML) 24 Page - NXP Semiconductors

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

Scheda tecnica Scarica

Link URL