Application Hint 38
Micrel
Application Hint 38
MICRF001 Crystal Selection
Micrel Crystal Suppliers
The following crystal manufacturers have been approved by
Micrel Semiconductor. Micrel requires that
approved
crystal
manufacturers test their crystals with the Micrel receiver over
the operating temperature range.
Please refer to
Application Note 32: Receiver Crystal Selec-
tion
for crystal parameters. MICRF001 crystal Q must be
greater then 115,000. ESR must be 100鈩?or less.
Suggested Crystal Manufacturers
Quartztek
Contact: Michael Carpenito
Precision Crystal Products
20 South 48th Avenue
Phoenix, AZ 95043
tel: (602) 272-7944
fax: (602) 233-2440
www.quartztek.com
Crystal Frequency
2.4107MHz
2.9847MHz
3.1990MHz
3.3208MHz
Part Number
F002A24107
F002A29847
F002A31990
F002A33208
Transmit Frequency
315MHz
390MHz
418MHz
433.92MHz
Crystal Testing
The following is a quick crystal test and is only applicable with
the Micrel receiver. An oscilloscope with a 300MHz, 8pF
scope probe is all that is necessary to test the basic operation.
In the
ac-coupled mode,
monitor the REF OSC pin and note
the voltage. A sine wave of amplitude greater than
鹵200mV
peak-to-peak for the MICRF001 must be observed. This
takes into account the loading effect of the scope probe.
Using a heat gun, apply heat and note that the reference
oscillator has not stopped oscillating or decreased in voltage
by more than 20%.
Surface mount crystal have not yet been qualified. Contact
Micrel applications for further details.
Abracon Corp
Contact: Chris Pollie
125 Columbia
Aliso Viejo, CA 92656
tel: (949) 448-7070
fax: (949) 448-8484
http://www.abracon.com
Crystal Frequency
2.4107MHz
2.9847MHz
3.1990MHz
3.3208MHz
Part Number
Transmit Frequency
315MHz
390MHz
418MHz
433.92MHz
Operating Frequency
Included are the common crystal frequencies used with the
Micrel receivers. Also included are the appropriate formulas.
Crystal accuracy must be to four decimal places
f
TX
f
LO
=
2.00
1
+
390
AB-2.4107MHz-20-D
AB-2.9847MHz-20-D
AB-3.1990MHz-20-D
AB-3.3208MHz-20-D
f
T
=
f
LO
130
, in MHz
Nominal f
TX
315.00MHz (f
T
= 2.4107MHz)
390.00MHz (f
T
= 2.9847MHz)
418.00MHz (f
T
= 3.1990MHz)
433.92MHz (f
T
= 3.3208MHz)
MMD Components
Contact: Jason Gann
32-B Mauchly
Irvine, CA 92618
tel: (949) 753-5888
fax: (949) 753-5889
www.mmdcomp.com
Crystal Frequency
2.4107MHz
2.9847MHz
3.1990MHz
3.3208MHz
Part Number
A15AC1-2.4107
A15AC1-2.9847
A15AC1-3.1990
A15AC1-3.3208
Transmit Frequency
315MHz
390MHz
418MHz
433.92MHz
QwikRadio is a trademark of Micrel, Inc. The QwikRadio ICs were developed under a partnership agreement with AIT of Orlando, Florida
Micrel, Inc. 鈥?1849 Fortune Drive 鈥?San Jose, CA 95131 鈥?USA 鈥?tel + 1 (408) 944-0800 鈥?fax + 1 (408) 944-0970 鈥?http://www.micrel.com
January 2000
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Application Hint 38
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