![]() |
![]() |
![]() |
|
|
|||||||
| Electronic Projects Design/Ideas/Reviews Are you building an electronic project or want to? Maybe you need some assistance? Come and submit your electronic questions here and let our experienced members find a solution. |
|
|
Thread Tools | Display Modes |
|
|
(permalink) |
|
planning on building a lm3886 chip amp, a BA3812L graphic equalizer and a VU bar graph meter(lm3914/15/16??)
which goes first the equalizer then the apm then tap into the outputs for the vu meter?? which bar graph driver chip=3914,15,16? buying the lme889 chip amp kit. just need toriod transformer. designing pcb for all but amp and power supply as the kit has these. need advice etc. |
|
|
|
|
|
|
(permalink) |
|
The LM3914 is a linear voltmeter. Low level audio is down only 20dB and the steps are huge. The steps at the loud end are crammed together.
The LM3915 has a logarithmic response the same as your hearing. Its lowest LED lights when the output is down 30dB (1/1000th the power) and each step is +3dB and is double the power. I have one with two LM3915 ICs cascaded for a 60dB range. The LM3016 is an odd-ball. The low volume steps are far apart and the loud steps are close together, something like an LM3914. The datasheet for the LM3915 shows two Peak Detector circuits. Without a peak detector then the level is jumping all over the place in real time which results in the LED display being a dim blur. The peak detector has a fast attack then a slight delay before dropping so your eyes can see the peaks.
__________________
Uncle $crooge |
|
|
|
|
| Bookmarks |
| Thread Tools | |
| Display Modes | |
|
|
|
|
||||
| Thread | Thread Starter | Forum | Replies | Latest |
| Audio / sound injection for in car computer | KCarPC75 | Electronic Projects Design/Ideas/Reviews | 1 | 5th January 2008 07:08 AM |
| Speedometer | Kiko | Micro Controllers | 131 | 29th November 2007 05:33 PM |
| Coupling with an audio output | fvnktion | Electronic Projects Design/Ideas/Reviews | 3 | 5th February 2007 09:37 PM |
| Gear Indicator.(need help to build one) | zx16v | Electronic Projects Design/Ideas/Reviews | 13 | 7th October 2006 06:08 PM |
| Audio Amplifier Designing Project | silverferro | Electronic Projects Design/Ideas/Reviews | 3 | 26th August 2004 10:04 AM |