Dave explains, shows, and measures a potentially big trap with using high value ceramic capacitors.
Is your 10uF capacitor really 10uF in your circuit? You might be shocked!
Those humble X7R caps you think are a "stable" dielectric? think again...
Class II and above ceramic capacitors can vary their capacitance drastically with DC bias voltage level and also the applied AC voltage.
Links:
http://www.murataamericas.com/murata/murata.nsf/promo_dcbias.pdf
http://www.avx.com/docs/masterpubs/mccc.pdf
http://www.ece.ucdavis.edu/vcl/asap/asap_v1/docs/X7R_C.pdf
http://psearch.murata.com/capacitor/product/GRM21BR60J106KE19%23.html
http://www.murata.com/products/design_support/simsurfing/outline.html
http://www.avx.com/SpiApps
Capacitor Tutorial - Ceramics & Impedance
https://www.youtube.com/watch?v=TDDoi70cxw0
The piezoelectric effect demonstrated:
https://www.youtube.com/watch?v=KFCRB4d991E
Forum: http://www.eevblog.com/forum/blog/eevblog-626-ceramic-capacitor-voltage-dependency-download/
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Another lengthy mailbag, with plenty of diverse stuff.
RCA Airnergy Bullshit Video: https://www.youtube.com/watch?v=P8s3Xjeg0sk
Forum: http://www.eevblog.com/forum/blog/eevblog-729-mailbag/
SPOILERS:
Kan Jam flying disc
Psion 3A Organiser
1974 808 RapidMan Calculator made in Canada.
Russian IN-9 Neon bargraph display tube.
Datasheet: http://exclusiv-store.com/tubes/in-9/1745_1.jpg
Info & characteristic curves: http://www.die-wuestens.de/rd/IN9-2.pdf
Wifi cellphone battery charging bullshit: https://www.kickstarter.com/projects/945803481/wave-a-cell-phone-that-charges-battery-with-wifi-s/description
RF Energy Harvesting. Can a WiFi signal light up a LED?
http://www.rfdiagnostics.com
Flir VP50 Non-Contact voltage detector.
Freescale PowerQuicc II security processor:
http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPC8248
APC Netbotz Room Monitor
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Fundamentals Friday
What is Sheet Resistance?
Did you know that the resistance of a square copper PCB trace is the same regardless of the size?
Dave explains the theory behind this rather counter-intuitive concept called Sheet Resistance, and demonstrates that it is in fact true.
What is the ohms per square of 1oz copper-clad PCB material and how can you use this concept to calculate the resistance of a PCB trace?
Thin Film Precision Resistor Network video: https://www.youtube.com/watch?v=Rxy-VpSDPg4
Forum: http://www.eevblog.com/forum/blog/eevblog-732-pcb-sheet-resistance/
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Teardown Tuesday
What's inside the world's worst and shittiest camcorder that costs a whopping $7.50 on Amazon?
The Global New Beginnings DV-136ZB 1.5" 3.1 MP Digital Video Camera
Mailbag: https://www.youtube.com/watch?v=NYWGXLuyH4M
Forum: http://www.eevblog.com/forum/blog/eevblog-595-world%27s-shittiest-camcorder-teardown/
Datasheet: http://www.icatchtek.com/files/SPCA1528A_PF_V1.pdf
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Dave attended the Cebit 2014 event in Sydney at Homebush Olympic Park. Here are some highlights.
The EX¹ the worlds first PCB printer. It prints silver conductive ink onto FR4, paper, mylar, or many other types of substrate.
https://www.kickstarter.com/projects/cartesianco/the-ex1-rapid-3d-printing-of-circuit-boards
GoFar, a wireless car monitoring startup.
http://www.gofar.co/
The University of Newcastle Robotics group NuBots:
http://www.newcastle.edu.au/research-and-innovation/centre/engineering-built-environment/newcastle-robotics-laboratory
Showcasing the robots use in the RoboCup challenge.
Forum: http://www.eevblog.com/forum/blog/eevblog-614-cebit-2014-highlights-download/
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What's inside a modern car airbag controller?
This is is from TRW and comes from a late model Hyundai.
Forum: http://www.eevblog.com/forum/blog/eevblog-517-car-airbag-controller-teardown/
Datasheets:
http://www.chemi-con.com/components/com_lcatalog/uploaded/4/7/6/19868903214d9b16734611d.pdf
http://www.ihs.com/news/renesas-h8sx1725f-vehicle.htm
http://www.epcos.com/inf/30/db/ind_2008/b82793c0_s0.pdf
http://www.datasheetarchive.com/dl/Datasheets-SW2/DSASW0023111.pdf
http://www.freescale.com/files/sensors/doc/data_sheet/MMA68xx.pdf
http://cache.freescale.com/files/sensors/doc/data_sheet/MMA685x.pdf
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00103810.pdf
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What's inside one of those omni-directional laser barcode scanners you use at the supermarket, and how does it work?
Motorola / Symbol LS9208
Datasheets:
Reflective Interrupter http://www.osram-os.com/Graphics/XPic0/00083379_0.pdf/SFH%209202,%20Lead%20%28Pb%29%20Free%20Product%20-%20RoHS%20Compliant.pdf
http://www.motorolasolutions.com/web/Business/Products/Bar%20Code%20Scanners/General%20Purpose%20Scanners/LS9208/_Documents/Static%20Files/LS9208.pdf
http://www.keil.com/dd/docs/datashts/atmel/at91fr4042.pdf
http://www1.futureelectronics.com/doc/RENESAS%20ELECTRONICS/DF2215RTE24V.pdf
Forum: http://www.eevblog.com/forum/blog/eevblog-636-omni-directional-laser-barcode-scanner-teardown/
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