Which do you think is the better +15V reg:
ST MicroElectronics L7815CV ...
Comparing their datasheets, it seems to me that the ST L7815CV is slightly superior, but I'm not really sure as I'm not an expert at reading datasheets. :-) Could someone please help me verify this?
Thanks a lot! :-)
Define 'better'...
Describe your application and its parameters...
Better would be more stable and clean output voltage under, say, 20% to 50% load conditions. This reg is for the analog supply to the opamps of a Delta 1010 soundcard/audio interface which has 8 analog inputs A/D, 8 analog outputs D/A, 1 S/PDIF stereo input, and 1 S/PDIF stereo output. The input voltage to the reg is 23V with a ripple of about 1.2V. Thanks.
The 340 has better line & load regulation shown on the datasheet than the 7815. For load: The 340 shows 35 mV,
5mA to 1.5A. The 7815 datasheet shows 150 mV for the same range. For line: the 340 shows 22 mV, the 7815 shows 150 mVIt may be that "better" as you defined it does not matter in your circuit.
Ed
I think you are comparing the LM340A. This is what confuses me about the datasheet. On the ordering info page, it lists the LM340A as available only for 5V. However, on the LM340A electrical characteristics (page 4) you can also see 12V and 15V. I did some searching on National's site and Newark, and it looks like the 12V and
15V of the LM340A are no longer in production. Only the LM340 without "A" is available for 12V and 15V. Therefore, the plain LM340 is what I would like to compare. Looking at the LM340 electrical characteristics on page 5 of the datasheet, it seems that the LM340 has inferior specs compared to the LM340A. Compared to the L7815, the LM340 has slightly inferior output noise voltage and ripple rejection specs. Based on this, I would like to confirm if you also think that the L7815 is superior, however slightly, to the LM340. Thanks.
Why don't you get a sample of both and compare their performance in the actual circuit...I hope you have advanced measurement methodology experience.
I think you have the cart and the horse reversed.
Your circuit defines the specs that the chip must provide. If either the 7815 or the 340 meets those specs, you're in business.
I think you may be asking which is best - car A, which goes
125 mph vs car B which goes 126 mph - when all you need is a car that goes 60 mph. And what is "best" between the two cars may be the one that has cupholders.Ed
u could go for a +12V supply than a 15V ram
ure/ds/2143/l7815c.pdf
u could go for +12V supply tahn a 15V
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