MC68HC908GR4MP datasheet(77/286 Pages) FREESCALE

No. de pieza	MC68HC908GR4MP

Descripción Electrónicos	M68HC08 Microcontrollers

PDF	286 Pages

Scroll/Zoom	100%

Fabricante Electrónico	FREESCALE [Freescale Semiconductor, Inc]

Página de inicio	http://www.freescale.com

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I/O Signals

MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7

Freescale Semiconductor

Figure 7-2. CGMC External Connections

7.4 I/O Signals

The following paragraphs describe the CGMC I/O signals.

7.4.1 Crystal Amplifier Input Pin (OSC1)

The OSC1 pin is an input to the crystal oscillator amplifier.

7.4.2 Crystal Amplifier Output Pin (OSC2)

The OSC2 pin is the output of the crystal oscillator inverting amplifier.

7.4.3 External Filter Capacitor Pin (CGMXFC)

The CGMXFC pin is required by the loop filter to filter out phase corrections. An external filter network is

connected to this pin. (See Figure 7-2.)

NOTE

To prevent noise problems, the filter network should be placed as close to

the CGMXFC pin as possible, with minimum routing distances and no

routing of other signals across the network.

OSC1

SIMOSCEN

CGMXCLK

CBYP

OSC2

CGMXFC

VDDA

Note: Filter network in box can be replaced with a 0.47

μF capacitor, but will degrade stability.

VDD

OSCSTOPENB

(FROM CONFIG)

RF1

CF2

CF1

VSSA

0.1

μF

MC68HC908GR4MP Datasheet(PDF) 77 Page - Freescale Semiconductor, Inc