CX5032SB12000F0FLJZZ AVX Corporation, CX5032SB12000F0FLJZZ Datasheet - Page 22

• Manufacturer Part Number: CX5032SB12000F0FLJZZ
• Description: CRYSTAL, SM, CX-96F, 12MHZ
• Manufacturer: AVX Corporation
• Series: CX5032SBr

Specifications of CX5032SB12000F0FLJZZ

• Operating Temperature Range: -30°C To +85°C
• Crystal Mounting Type: SMD
• Crystal Case Type: 5
• Frequency: 12MHz
• Frequency Tolerance: ± 10ppm
• Load Capacitance: 10pF
• Frequency Stability: ± 10ppm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

(2) Changes of load capacitance and oscillation frequency
3. Crystal oscillation circuit
(1) CMOS fundamental crystal oscillation circuit
As shown above, the series resonance frequency of the crystal
unit changes with load capacitance C
In the actual oscillation circuit, however, fine adjustments of
oscillation frequencies are carried out by varying C
trimmer capacitor or the like. The following figure shows an
example of load capacitance characteristics. The slope of the
characteristics varies depending on the frequency, shape, the
number of overtone mode, etc.
As shown above, the series resonance frequency of the crystal
The figure on the right shows a standard CMOS inverter crystal
oscillation circuit for oscillating crystal unit with fundamental mode.
* Rx is an element to reduce excitation current of the crystal unit
preventing frequency fluctuation, but Rx is not used in some cases.
Characteristics of the circuit when load capacitances C
are changed under the condition of C
figure on the right.
It is not desirable that the excessive increase of the value of
condenser leads to a decrease of the negative resistance
resulting in increasing the possibility of oscillation failure.
Rd mainly adjusts frequency characteristics of the negative
resistance and is used to prevent oscillating by third Overtone
mode. In case of a bigger circuit of the negative resistance,
there is a case it is used to prevent the abnormal oscillation.
Handling Notes
L
1
of the oscillation circuit.
= C
2
are shown in the
L
1
by the
and C
- 55 -
2
Variation of negative resistance with condenser capacity
()
()
Frequency characteristics of negative resistance
CMOS fundamental crystal oscillation circuit
800
700
600
500
400
300
200
100
-100
-200
-500
-1K
-2K
-5K
-10K
0
0
-100
-200
-500
-1K
-2K
-5K
-10K
2
C
1
Xtal
0
4
10
R
f
= 1M
10
6
Condenser capasityC (C
Rx
20
20
Frequency(MHz)
8
C
Rd
1
C
=C
2
30
30
2
10
=10pF
Load capacity characteristic
Buffer
1
=C
40
2
12
)(pF)
40
Resistance of Rd
3.5 to 6.9MHz=2.2k
7.0 to 16MHz=220
50
16.0MHz
10.0MHz
3.579545MHz
14
50
16
C
L
(pF)
60