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From the specs
So yes in the document that comes with the chip it does mention that the "reference voltage" is -1.25V when the conditions are such that the I_o is between 10mA and 1.5A.
I also see a row called "Minimum load current to maintain regulation" which itself has a maximum value of...
So using 120Ω for R1 gives about 1500Ω for R2 with similar power requirements (1/4 watt for R1 and 1 watt for R2 to be very safe). However I did not find anything in the documentation saying why I should use 120 over any other value. I'm just trying to understand how you came up with that value...
Okay, thanks for the clarification. I thought you were saying that this chip that you suggest was also a DC/DC charge pump--or maybe it is, but it is isolated where as the 7660 is not. I think 1W will be plenty of power. Do you know where I can find this part on Digi-Key or where I can buy it in...
Hello,
If you have a negative voltage like say -20V and you want to get it down to -17V (or technically this is up since -17 is greater than -20) would you use the LM337 in this case?
The current would be about 10mA - 13mA in my project with an absolute maximum of 20mA if that matters...
I see you didn't read the linked PDF in my original post. The first page in large letters describes the chip as a "SUPER CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER".
Thanks for the information. I tried looking for a similar part on Digi-Key but could not find anything. Also it looks like that part...
Thanks
I am working with +5V input right now and would like to stick with just that if possible. I am not familiar with SMPS. I read about it on Wikipedia real quick. For my project I am using a wall plug-in transformer from Radio Shack that has a selectable voltage output (it can go up to...
I have read over the documentation for the TC7660 chip by Microchip Technology, and would like to know if I am reading this right.
Can I chain 4 or 5 of these chips together with a +5V initial input and get either -20V or -25V output ?
I need -17V for a project so I was thinking I could...
Hello,
I have been tinkering with electronics for a while now and I recently purchased an cheap LCD display which needs a -22V @ 13mA and -17V @ unspecified current in addition to the standard +5V @ 10mA for logic. So I have a wall transformer with selectable output's and already have a...
I recently purchased an LCD display from All Electronics. The exact part I purchased is available at this link for your reference. The documentation which is on that same page is a very hard to read PDF. After looking it over many times and reading the documentation for other similar devices on...
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