kjoephi
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Hi there, I have search on internet to find that 8 bit 2:1 demux but no luck. can any body tell me the part number? thanks, regards Pramono
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Hi all, I got a little confused with the data selector. im looking for a data selector to select 8 bit of data comming from a micro controller port going to one of two led driver IC ULN2803. i plan to use 2 of quadruple 1 to 2 data selector. this means 1 bit from microcontroller can go to the input of one the driver IC. i've search the net, but all i found is data selector that select 2 input to 1 output. this is the oopsite type of fuction that i need. My question are : 1. what is the part number for the IC that i need? 2. can i use 2 input to 1 output data selector as a 1 input to 2 output data selector? best regards Pramono
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Alarm sound detector schematic
kjoephi replied to kjoephi's topic in Electronic Projects Design/Ideas
Hi there Guru... Im thinking to use some kind of bandpass filter with 4 Khz as the center frequency and use high value of Q. I got the article from http://www.electronics-tutorials.com/filters/active-bandpass-filters.htm but i think the opamp used is double supply opamp (+ gnd -). i dont know how to convert this circuit for a single supply opamp such as LM358. can any body give me a hand? thank you -
Alarm sound detector schematic
kjoephi replied to kjoephi's topic in Electronic Projects Design/Ideas
Hi there, guru.. i agree about "Many sounds contain 3kHz and 4Khz frequencies, including noise". can you help me to share info or internet link, about how to design a frequency filter amplifier using 2 opamp to let only 4 Khz -
Hi all, i'm a newbie. can any body please share me some information about demultiplxer IC. im looking for a 4 to 16 bit demultiplexer IC with active high output. normally i use DM74LS154N which gives active low output. I also looking for an 8 bit led driver IC to drive 200 mA current. or a darlington transistor array (8 or 16 transistor each single chips) i have try to find it on www.alldatasheet.com but no luck. can any body help me please? thank you :)
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Hi all, im a newbie. :-[ can anybody help me to get a schematic for alarm cound detector. basically it's only use to give a digital output high when it detects a sound with certain frequency. in this chase is 3 to 4 Khz alarm sound. thank you :)