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#1
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Please see the pdf at:alt.binaries.schematics.electronic dated 5/8 8:08 PM.
Has anyone see this technology used used at RF or IF? tnx -- 73 Hank WD5JFR |
#2
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![]() Good day I am the one who made the post. I've been involved in rf for 30 years and have actively followed piezotransformer technology since first reading about them in EDN Magazine in 1999. They are unusual beasts for sure. The resonant frequency can be controlled by the thickness of the material, as any piezomaterial can. For fine tuning, the size of the electrodes on the primary side can be trimmed. Q's are not nearly as high as quartz, so the ultimate frequency stability honors go to quartz. They can be useful for some rf aps, up to 3 Mhz, although the vast majority of presently made devices operate in the 200 Khz to 40 Khz range. The resonant frequency does shift slightly with varying load impedances however.. As transformers however, they excel. Conventional magnetic/copper transformers cannot even start to deliver step up ratios anywhere near those of PZT's. Unknown to many is the fact that they can convert low impedance to high impedance OR visa versa. I have just located a source of piezotransformers that have totally isolated primary and secondary terminals (4 terminals) instead of the common 3 terminal types presently available. Digi-Key sells the Panasonic units in their current catalog. Hope this info helps. Mebart Mon, 09 May 2005 14:34:51 GMT, "Henry Kolesnik" wrote: Please see the pdf at:alt.binaries.schematics.electronic dated 5/8 8:08 PM. Has anyone see this technology used used at RF or IF? tnx |
#3
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![]() Good day I am the one who made the post. I've been involved in rf for 30 years and have actively followed piezotransformer technology since first reading about them in EDN Magazine in 1999. They are unusual beasts for sure. The resonant frequency can be controlled by the thickness of the material, as any piezomaterial can. For fine tuning, the size of the electrodes on the primary side can be trimmed. Q's are not nearly as high as quartz, so the ultimate frequency stability honors go to quartz. They can be useful for some rf aps, up to 3 Mhz, although the vast majority of presently made devices operate in the 200 Khz to 40 Khz range. The resonant frequency does shift slightly with varying load impedances however.. As transformers however, they excel. Conventional magnetic/copper transformers cannot even start to deliver step up ratios anywhere near those of PZT's. Unknown to many is the fact that they can convert low impedance to high impedance OR visa versa. I have just located a source of piezotransformers that have totally isolated primary and secondary terminals instead of the common 3 terminal types presently available. Digi-Key sells the Panasonic units in their current catalog. Hope this info helps. Mebart On Mon, 09 May 2005 14:34:51 GMT, "Henry Kolesnik" wrote: Please see the pdf at:alt.binaries.schematics.electronic dated 5/8 8:08 PM. Has anyone see this technology used used at RF or IF? tnx |
#4
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Hey Mebart, and a good day to you too. Mehank
On a more serious note, thanks for both posts. I took a look at the Panasonic at Digikey and it looks like they're made for ~50:1 stepup to light up displays. http://dkc3.digikey.com/PDF/T052/1522.pdf Have you ever checked the passband of one? -- 73 Hank WD5JFR Mebart wrote in message ... Good day I am the one who made the post. I've been involved in rf for 30 years and have actively followed piezotransformer technology since first reading about them in EDN Magazine in 1999. They are unusual beasts for sure. The resonant frequency can be controlled by the thickness of the material, as any piezomaterial can. For fine tuning, the size of the electrodes on the primary side can be trimmed. Q's are not nearly as high as quartz, so the ultimate frequency stability honors go to quartz. They can be useful for some rf aps, up to 3 Mhz, although the vast majority of presently made devices operate in the 200 Khz to 40 Khz range. The resonant frequency does shift slightly with varying load impedances however.. As transformers however, they excel. Conventional magnetic/copper transformers cannot even start to deliver step up ratios anywhere near those of PZT's. Unknown to many is the fact that they can convert low impedance to high impedance OR visa versa. I have just located a source of piezotransformers that have totally isolated primary and secondary terminals instead of the common 3 terminal types presently available. Digi-Key sells the Panasonic units in their current catalog. Hope this info helps. Mebart On Mon, 09 May 2005 14:34:51 GMT, "Henry Kolesnik" wrote: Please see the pdf at:alt.binaries.schematics.electronic dated 5/8 8:08 PM. Has anyone see this technology used used at RF or IF? tnx |
#5
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Hi Hank,
I've never checked it specifically....and have only ballpark figures for Q. There is one other oddity that you probably should be aware of.... The output voltage is not in the same phase as the input voltage. While this isn't a great problem, do be aware that the phase difference between the input/output also changes with temperature, and resistive loading. This totally precludes using them in a power oscillator circuit, which is a bummer. They would be so simple to drive if the phase difference was relatively constant:: I just read about a new driver chip that constantly measures and corrects for this phase difference, and in so doing the device always operates at peak efficiency. There are other piezoceramics that are usable as filters and such, goggle for them. Regards, Mebart On Mon, 09 May 2005 18:56:21 GMT, "Henry Kolesnik" wrote: Hey Mebart, and a good day to you too. Mehank On a more serious note, thanks for both posts. I took a look at the Panasonic at Digikey and it looks like they're made for ~50:1 stepup to light up displays. http://dkc3.digikey.com/PDF/T052/1522.pdf Have you ever checked the passband of one? |
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