Circuit Design

CX-6V-SM- Tray Pack (Standard)

- 16mm tape, 178mm or 330mm reels

(Optional) per EIA 481

Packaging

Order Code

CX-6

“S” if special

or custom design

Blank if standard

Frequency

SM1

SM2

SM3

Calibration

Tolerance*

@ 25°C

A, B, C

1.0MHz

-SM1

Temperature

Range:

C = Commercial

I = Industrial

M = Military

S = Specify

(A /

I )

C = Ceramic Lid

Blank = Glass Lid

*For other calibration

tolerances enter

figure in ppm

Typical Pierce Oscillator Application

The low profile CX miniature surface-mount crystal is ideal for small,

battery operated portable products. The CX crystal designed in a

Pierce oscillator (single inverter) circuit has a very low current

consumption with high stability. A conventional HCMOS Pierce

oscillator circuit is shown below. The crystal is effectively inductive

and in a Pi network with C and C which provides the additional

phase-shift necessary to sustain oscillation. The oscillation frequency

(f ) is 15ppm to 150ppm above the crystal’s series resonant

frequency (F ).

R is used to limit the crystal’s drive level by forming a voltage

divider between R andC.R also stabilizes the oscillator against

changes in the amplifiers output resistance (R ). R should be

increased for higher voltage operation.

The CX crystal calibration tolerance is influenced by the effective

circuit capacitances, specified as the load capacitance (C .) C is

approximately equal to:

12

0

S

A

A1

A

0A

LL

Drive Level

Load Capacitance

C =

Cx C

C+ C

2

2

1

1

LS

C

+

NOTE: C and C include stray layout capacitance to ground. C is

the stray shunt capacitance between the crystal terminals. In

practice, the effective valus of C will be less than that calculated

fromC,C,and CS values due to the effect of the amplifier output

resistance. C should be minimized.

The oscillation frequency (f ) is approximately equal to:

12

S

L

12

S

0

Where F = Series resonant frequency of the crystal

C = Motional Capacitance

C = Shunt Capacitance

S

1

0

f =

2(C+ C)

0L

1+

Conventional HCMOS Pierce Oscillator Circuit

CX-2

Buffer

Amplifier

Osc.

Freq. (Fo)

C

Terminations

Designation

SM1

Gold Plated

SM2

Nickel, Solder Plated

SM3

Nickel, Solder Plated and Solder Dipped

Termination

Solder Pad Layout

1.78

3.05

5.46

+44(0)1460 230000

+44(0)1460 230001

sales@euroquartz.co.uk

www.euroquartz.co.uk

Telephone:

Fax:

Email:

Web:

CX MINIATURE CRYSTALS

Page

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CX-6V-SM

800kHz to 1.35MHz

ULTRA-LOW PROFILE

MINIATURE SMD CRYSTAL

CX-6V-SM

800kHz to 1.35MHz

ULTRA-LOW PROFILE

MINIATURE SMD CRYSTAL