ETC APPLICATIONHINT34

Application Hint 34
Micrel
Application Hint 34
MICRF002/RF011/RF022 Ceramic Resonators
Ceramic Resonator Series Resistance
Ceramic Resonator Availability
An on-board oscillator within the MICRF002, MICRF011,
and MICRF022, together with an externally connected resonator or clock signal, establishes the operating frequency of
the MICRF002/RF011/RF022. When using a resonator (ceramic resonator or crystal), its series resistance should be
minimized to ensure oscillation. If the resonator series
resistance is too great, the oscillator may operate at a
diminished peak-to-peak level or may fail to oscillate entirely.
Micrel recommends that series resistance for ceramic resonators and crystals not exceed 50Ω and 100Ω, respectively.
A family of ceramic resonators manufactured by Murata
Electronics, featuring low series resistance, has been characterized with the MICRF011/RF022/RF002. This characterization was performed with the IC operating in “sweep” mode.
These standard resonators (see table on following page)
provide a convenient solution for many common frequencies.
Sample quantities of standard resonators are available from
Murata Electronics (www.murata.com) for rapid prototyping.
Murata can also provide resonators at custom frequencies for
high-volume applications.
Resonator Frequency = fT =
fTX
64.25
Receive
Frequency
Resonator
Frequency
Murata
Part No.
315MHz
4.903MHz
CST0490MGO3052
390MHz
6.07MHz
CST5607MGO3052
418MHz
6.506MHz
CSTS0650MGO3052
433.92MHz
6.754MHz
CSTS0675MGO3052
Ceramic Resonator Samples
Available Through
Micrel Semiconductor
Also see full table on following page.
QwikRadio is a trademark of Micrel, Inc. The QwikRadio ICs were developed under a partnership agreement with AIT of Orlando, Florida
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
March 2000
1
Application Hint 34
Application Hint 34
4.747MHz
305MHz
TEL
+ 1 (408) 944-0800
FAX
+ 1 (408) 944-0970
2
WEB
CSTS0675MGA03052
Note 5
CSTS0666MGA03052
Note 5
CSTS0650MGA03052
Note 5
CSTS0645MGA03052
Note 5
CSA6.22MGA05052
CSA6.17MGA05052
CSA6.07MGA05052
CSA6.02MGA05052
CSA4.90MGA05052
CSA4.74MGA05052
CSA4.66MGA05052
Leaded
Automotive Grade (Note 3)
CSA4.66MGCA05052-TC
CSA4.66MGCMA05052-TC
Note 4
SMD
Automotive Grade (Note 3)
CSTCC6.75MG03052-TC
Note 6
CSTCC6.66MG03052-TC
Note 6
CSTCC6.50MG03052-TC
Note 6
CSTCC6.45MG03052-TC
Note 6
CSTCC6.22MG03052-TC
Note 6
CSTCC6.17MG03052-TC
Note 6
CSTCC6.07MG03052-TC
Note 6
CSTCC6.02MG03052-TC
Note 6
CSTCC6.75MGA03052-TC
Note 6
CSTCC6.66MGA03052-TC
Note 6
CSTCC6.50MGA03052-TC
Note 6
CSTCC6.45MGA03052-TC
Note 6
CSTCC6.22MGA03052-TC
Note 6
CSTCC6.17MGA03052-TC
Note 6
CSTCC6.07MGA03052-TC
Note 6
CSTCC6.02MGA03052-TC
Note 6
CSAC4.90MGC05052-TC
CSAC4.90MGCA05052-TC
CSAC4.90MGCM05052-TC CSAC4.90MGCMA05052-TC
Note 4
Note 4
CSAC4.74MGC05052-TC
CSAC4.74MGCA05052-TC
CSAC4.74MGCM05052-TC CSAC4.74MGCMA05052-TC
Note 4
Note 4
CSAC4.66MGC05052-TC
CSAC4.66MGCM05052-TC
Note 4
SMD
Consumer Grade (Note 2)
MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131
Consumer grade is for the –20˚C to +80˚C operating range and is intended for nonautomotive applications.
Automotive grade, indicated by the “A” part number suffix, is for the –40˚C to +125˚C operating range and is intended for automotive applications.
CSACx.xxMGCxxxxx-TC is a melph package (cylindrical package). If a round component is of a concern, Murata can recommend the CSACx.xxMGCMxxxxx-TC which
adds a square plastic sleeve to the middle of the package. The square sleeve allows for automatic placement without a cylinder placement nozzle.
CSTSxxxxMG(A)xxxxx is a three-terminal resonator. CAUTION: The middle terminal or lead should not be connected or grounded.
CSTCCx.xxMG(A)xxxxx-TC is a three terminal resonator. CAUTION: The middle terminal should not be connected or grounded.
Note 2.
Note 3.
Note 4.
Note 5.
Note 6.
Murata sorts the above recommended resonators for 100% operation with the Micrel MICRF002, MICRF011, and MICRF022. Sorting insures stable oscillation and
startup over resonator production variation and operating temperature range. It also insures that the specified initial oscillator frequency of the resonator will be achieved
with the Micrel MICRF002, MICRF011, and MICRF022. Unsorted resonators could experience general stability problems and repeating initial oscillation frequency shifts
due to the difference between the Micrel ICs and the standard resonator test circuit used in resonator production.
CSTS0675MG03052
Note 5
CSTS0666MG03052
Note 5
CSTS0650MG03052
Note 5
CSTS0645MG03052
Note 5
CSA6.22MG05052
CSA6.17MG05052
CSA6.07MG05052
CSA6.02MG05052
CSA4.90MG05052
CSA4.74MG05052
CSA4.66MG05052
Leaded
Consumer Grade (Note 2)
Note 1.
6.754MHz
433.92MHz
6.506MHz
418MHz
6.662MHz
6.459MHz
415MHz
428.02MHz
6.226MHz
400MHz
6.176MHz
6.070MHz
390MHz
396.8MHz
6.023MHz
387MHz
4.903MHz
4.669MHz
300MHz
315MHz
Resonator
Frequency
Receive
Frequency
Murata Ceramic Resonators for the Micrel MICRF002, MICRF011, and MICRF022 (Note 1)
Application Hint 34
Micrel
http://www.micrel.com
USA
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
© 2000 Micrel Incorporated
March 2000