Has anyone made an LED driver based on LM3463 6 channel driver IC?
- Thread starter tomservo
- Start date
Hey Rick!
I'm runnin' low on them myself, I'm down to about 150 left. That's still 150 more than DigiKey's got :lmao:. How are yours holding up?
Hi O2,... I only built one board but it worked well until it went for a dip in the tank...lights out lol. I have the resistors for 700 and 1400ma output and made a 700 for the 50w Dream Chip I had. I really liked the board design with the cat outlets and the 10 pin molex conn. on the board. Thanks again for all the help!---Rick
I've got a new A6211 based led driver in the works..... LOL- It's really nothing too crazy.... just a little evolution going on. As you know, I recently created a new 6 channel LDD-H PcB for use with the new BlueFish Mini WiFi Led controller. I'm currently using 2 of them over my tank, but I can't stand using LDD's after putting so much work into my own A6211 based drivers. So this latest design is along the same lines, but uses a A6211 based driver, and a few added twists. I absolutely love the BlueFish Mini Led controller, but it's 3.3V signal voltage & 3ma current limit per channel has to be improved. My new design gets around those limits, as I've added a six channel Hex Buffer/translator to the mix. The BF Mini's weak 12Bit PWM signals get stepped-up to a full 5V/20ma, so voltage drops over long signal cable runs will no longer be an issue. This one's also got an Arduino Nano on board for 25Khz fan control.
I just got the boards in yesterday from China, so I'll be soldering up a couple of them over the next couple of days. Should be fun.....
Here's a photo of the design.
LOL- They're not that elusive anymore.......... Digikey has 63,000 of 'em. I don't think they'll be running out of them anytime soon.:dance:
If you have any soldered up spares let me know. Just hastily soldered together a 6 channel rig for my display when the old VHOs smoked last week, only able to run on/off at the moment on handfull of LPC drivers and one ELN for whites that I had laying around.
Had an uber build planned using 208 LEDs and the stormx with 30+ LDD drivers but that would have took to long, and so far I'm not too disappointed with the color using only the vero chip for whites at the moment. Time will tell though as corals adapt and colors undoubtedly shift a bit.
ended up settling for the time being on a measly 49 blue and violets, plus 4 vero 10s......but no control....
This would be almost plug and play with my wireing for the basic control of lights and fans (all that I really care about anyway).though now that I think about it can the bluefish mini be configured from a laptop? don't have a tablet or smart phone so that would put a wrench into things........
fall back I suppose is my original plan of a hacked storm X getting rid of most of the menu to allow for smarter fan controls and some other sensor readouts and additional light period controls....that's a heck of a long way off though given my free time as of late and limited programming skills.
Way to keep us on the edge of our seats O2! (but don't you have a day job and/or someone nagging you to stay out of the garage? How do you find so much time to tinker?).
I ordered 5 Pcb's but I only need 2. I suppose that I'll build out the leftover 3 and sell them off to whoever wants them
.Yes, you can use a laptop. There's a free App called "Arc Welder" available from Google Play that allows you to run Android apps from your PC. https://developer.chrome.com/apps/getstarted_arc
LOL- My "day job" offers plenty of "down time" to pursue this stuff, and my wife actually encourages me to "get out to the garage and invent something". She seriously thinks that my "tinkering" will payoff big someday!:lolspin:
I just happen to have a canopy laying on the floor right now......fits a 55 gal...........wouldn't be worth shipping though, it's only made out of cheap pine boards.......
Everyone needs a frag tank to grow out those expensive frags that will "pay for the hobby"....at least that's what I keep telling myself to get to sleep at night....... :lolspin:
I believe in the "more's better" motto. The Heat sinks are positioned in such a way that they're actively cooled by the same fans used to cool the leds themselves. Each A6211 driver IC's thermal tab is connected to the underside of the PcB through a large, solder filled "via". The soldered via is clamped to the heat sink with just a small amount of thermal grease in between.
From the Allegro calculator, it appears that total switching losses cause the IC to drop about 1.22 watts of power when driving 1400ma. My heat sinking seams to work well, as the driver IC's barely feel warm to the touch after many hours of operation. Here's what the Allegro design tool has to say-
<table border="0" cellpadding="0" cellspacing="0" width="656"><colgroup><col style="mso-width-source:userset;mso-width-alt:9435;width:194pt" width="258"> <col style="mso-width-source:userset;mso-width-alt:2742;width:56pt" width="75"> <col style="mso-width-source:userset;mso-width-alt:2486;width:51pt" width="68"> <col style="mso-width-source:userset;mso-width-alt:2230;width:46pt" width="61"> <col style="mso-width-source:userset;mso-width-alt:7094;width:146pt" width="194"> </colgroup><tbody><tr style="height:15.75pt" height="21"> <td colspan="3" class="xl64" style="height:15.75pt; width:301pt" height="21" width="401">A6211 External Component Value Calculator </td> <td style="width:46pt" width="61">
</td> <td style="width:146pt" width="194">
</td> </tr> <tr style="height:15.75pt" height="21"> <td class="xl65" style="height:15.75pt" height="21">saved for 36V1400ma drive</td> <td class="xl64">
</td> <td class="xl89">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:15.75pt" height="21"> <td class="xl66" style="height:15.75pt" height="21">Notes:</td> <td class="xl64">
</td> <td class="xl64">
</td> <td>
</td> <td>
</td> </tr> <tr style="mso-height-source:userset;height:12.75pt" height="17"> <td class="xl67" style="height:12.75pt" height="17">1. Enter system data into grey cells.</td> <td class="xl64">
</td> <td class="xl64">
</td> <td>
</td> <td>
</td> </tr> <tr style="mso-height-source:userset;height:12.75pt" height="17"> <td colspan="4" class="xl106" style="height:12.75pt; width:347pt" height="17" width="462">2. After component values are calculated, then enter preferred values into blue cells.</td> <td>
</td> </tr> <tr style="mso-height-source:userset;height:12.75pt" height="17"> <td class="xl67" colspan="3" style="height:12.75pt;mso-ignore:colspan" height="17">3. A performance summary is then generated (green cells).</td> <td>
</td> <td>
</td> </tr> <tr style="height:15.75pt" height="21"> <td colspan="2" style="height:15.75pt;mso-ignore:colspan" height="21">4. Warning messages, if any, are listed below in Red</td> <td class="xl68">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:15.75pt" height="21"> <td style="height:15.75pt" height="21">
</td> <td class="xl68">
</td> <td class="xl68">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl90" style="height:12.75pt" height="17">Description</td> <td class="xl70">Symbol</td> <td class="xl70">Value</td> <td class="xl69">Unit</td> <td class="xl69">Remark</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Input supply voltage</td> <td class="xl71">Vin</td> <td class="xl100" align="right">48</td> <td>V</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Number of LEDs in output string</td> <td class="xl71">N</td> <td class="xl100" align="right">1</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Forward voltage of each LED</td> <td class="xl71">V_f</td> <td class="xl100" align="right">36</td> <td>V</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Output LED string voltage</td> <td class="xl71">Vout</td> <td class="xl73" align="right">36.2</td> <td>V</td> <td>Including sense voltage of ~0.2V</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">LED current required</td> <td class="xl71">i_LED</td> <td class="xl100" align="right">1.4</td> <td>A</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Ripple current as % of average current</td> <td class="xl71">
</td> <td class="xl100" align="right">30</td> <td>%</td> <td>typically 20-40% of i_LED</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">EstimatedLED ripple current</td> <td class="xl71">
</td> <td align="right">0.42</td> <td>Apk-pk</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Forward voltage drop of schottky diode</td> <td class="xl71">Vd</td> <td class="xl100" align="right">0.7</td> <td>V</td> <td>typically 0.5 - 0.7V</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Sense resistor average voltage (typ. 0.2V)</td> <td class="xl71">Vs</td> <td align="right">0.2</td> <td>V</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Min T_on (up to 0.15uS)</td> <td class="xl71">
</td> <td align="right">0.15</td> <td>uS</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Min T_off (up to 0.150S)</td> <td class="xl71">
</td> <td align="right">0.15</td> <td>uS</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Frequency selection constant</td> <td class="xl71">k</td> <td class="xl88" align="right">0.0139</td> <td>
</td> <td class="xl88">freq=1 / (k * (Ron+5))</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated duty Cycle</td> <td class="xl71">D</td> <td class="xl74" align="right">75.8%</td> <td>
</td> <td>D=(Vo+Vd)/(Vi+Vd)</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated sense resistor value</td> <td class="xl71">
</td> <td class="xl75" align="right">0.143</td> <td>Ohm</td> <td class="xl76"> Rs = Vs / i_LED </td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl92" style="height:12.75pt" height="17">Enter preferred sense resistor value</td> <td class="xl71">Rs</td> <td class="xl101">0.140</td> <td>Ohm</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated LED current</td> <td class="xl71">i_LED</td> <td class="xl77">1.429</td> <td>A</td> <td>i_LED = Vs / Rs</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Desired switching frequency</td> <td class="xl71">
</td> <td class="xl102" align="right">0.45</td> <td>MHz</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated Ton selection resistor</td> <td class="xl71">
</td> <td class="xl78" align="right">154.9</td> <td>kOhm</td> <td class="xl88">Ron = 1 / (f_sw* k) -5</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl92" style="height:12.75pt" height="17">Enter preferred resistor value</td> <td class="xl71">Ron</td> <td class="xl103" align="right">154.9</td> <td>kOhm</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Actual switching frequency</td> <td class="xl71">f_sw</td> <td class="xl79" align="right">0.45</td> <td>MHz</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated SW on-time</td> <td class="xl71">Ton</td> <td class="xl80" align="right">1.676</td> <td>uS</td> <td>Ton = k * (Ron+5) * Vout/Vin</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl93" style="height:12.75pt" height="17">
</td> <td class="xl71">
</td> <td class="xl80">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated SW off-time</td> <td class="xl71">Toff</td> <td class="xl80" align="right">0.546</td> <td>uS</td> <td>Toff = 1/f_sw - Ton</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl93" style="height:12.75pt" height="17">
</td> <td class="xl71">
</td> <td class="xl80">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated inductor value</td> <td class="xl71">
</td> <td class="xl78" align="right">47.1</td> <td>uH</td> <td>L = (Vin-Vout) * Ton / i_ripple</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl92" style="height:12.75pt" height="17">Enter preferred inductor value, L</td> <td class="xl71">L</td> <td class="xl103" align="right">47.0</td> <td>uH</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated ripple current</td> <td class="xl71">i_ripple</td> <td class="xl75" align="right">0.421</td> <td>A</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Minimum inductor current rating</td> <td class="xl71">i_sat</td> <td class="xl75" align="right">1.967</td> <td>A</td> <td>Including 20% headroom</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculate ripple voltage</td> <td class="xl71">V_ripple</td> <td class="xl80" align="right">0.059</td> <td>Vpk-pk</td> <td>Keep ripple voltage >= 0.02V</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl81" style="height:12.75pt" height="17">
</td> <td>
</td> <td class="xl82">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl69" colspan="2" style="height:12.75pt;mso-ignore:colspan" height="17">Performance summary with preferred values</td> <td class="xl82">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Switching frequency</td> <td>
</td> <td class="xl83" align="right">0.45</td> <td>MHz</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Average LED current with Rs= mOhm</td> <td>
</td> <td class="xl84" align="right">1.429</td> <td>A</td> <td class="xl85">
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">LED ripple current with L= 47uH</td> <td>
</td> <td class="xl84" align="right">0.421</td> <td>Apk-pk</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Ripple current as % of average current</td> <td>
</td> <td class="xl86">29</td> <td>%</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td style="height:12.75pt" height="17">
</td> <td>
</td> <td class="xl87">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl99" style="height:12.75pt" height="17">Update on April 10, 2012:</td> <td>
</td> <td class="xl87">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl94" style="height:12.75pt" height="17">Power Loss Calculation (for IC only)</td> <td>
</td> <td class="xl87">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Input Voltage</td> <td class="xl71">Vin</td> <td class="xl104">48</td> <td>V</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Thermal Resistance</td> <td class="xl71">R_θJA</td> <td class="xl104">35</td> <td>°C/W</td> <td>SOIC-8 pn 4-layer PCB</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">SW on-restsiance at 25°C</td> <td class="xl71">R_DSON</td> <td class="xl104">0.4</td> <td>Ohm</td> <td>0.25 typ, 0.4 max</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Resistance increase at hot</td> <td class="xl71">
</td> <td class="xl105">60%</td> <td>
</td> <td>40% at 100C, 60% at 125C</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Output LED string voltage</td> <td class="xl71">Vout</td> <td class="xl91">36.2</td> <td>V</td> <td>from previous section</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated duty Cycle</td> <td class="xl71">D</td> <td class="xl74" align="right">75.8%</td> <td>
</td> <td>D=(Vo+Vd)/(Vi+Vd)</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Calculated LED current</td> <td class="xl71">i_LED</td> <td class="xl91">1.4285714</td> <td>A</td> <td>from previous section</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">SW Conduction Loss</td> <td class="xl71">P_cond</td> <td class="xl96">0.99</td> <td>W</td> <td>i^2 * R * D</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">
</td> <td class="xl71">
</td> <td class="xl91">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Switching frequency</td> <td class="xl71">f_sw</td> <td class="xl91">0.4499215</td> <td>MHz</td> <td>from previous section</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">SW rise time</td> <td class="xl71">T_rise</td> <td class="xl95">5</td> <td>nS</td> <td class="xl99">5nS typical from SW waveform</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">SW fall time</td> <td class="xl71">T_fall</td> <td class="xl91">10</td> <td>nS</td> <td>10ns typical</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">SW switching loss</td> <td class="xl71">P_sw</td> <td class="xl96">0.23</td> <td>W</td> <td>Vin * iout * (t_r+t_f)/2 * f_sw</td> </tr> <tr style="height:12.75pt" height="17"> <td style="height:12.75pt" height="17">
</td> <td>
</td> <td class="xl95">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Total Power Loss in SW</td> <td class="xl71">P_total</td> <td class="xl96">1.22</td> <td>W</td> <td>P_cond + P_sw</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Temperature Rise</td> <td class="xl71">delta_T</td> <td class="xl98">42.7</td> <td>°C</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Ambient Temp</td> <td class="xl71">T_a</td> <td class="xl104">25</td> <td>°C</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl91" style="height:12.75pt" height="17">Estimated Junction Temp</td> <td class="xl71">T_j</td> <td class="xl97">67.7</td> <td>°C</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td style="height:12.75pt" align="left" height="17" valign="top">
<table cellpadding="0" cellspacing="0"> <tbody><tr> <td style="height:12.75pt;width:194pt" height="17" width="258">
</td> </tr> </tbody></table> </td> <td>
</td> <td class="xl87">
</td> <td>
</td> <td>
</td> </tr> <tr style="height:12.75pt" height="17"> <td class="xl65" style="height:12.75pt" height="17">Note: power discipation from IC bias supply not included</td> <td style="height:12.75pt;width:56pt" height="17" width="75">
</td> <td>
</td> <td>
</td> <td>
</td> </tr> </tbody></table>
