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  1. Yes as per switch specs max power consumption about 11W for all rails And probably 2A is not enought for 1V rail but it is impossible to have 5+A @3.3V
  2. 5-7A!!! Are you serios?? i think problem not with the current limit but with the way of external regulator connection, if onbord regulators not disconnected from the load (reverse current protection can cause the problem). @RickyV How did you connect Lt3045 regulators to the BS??
  3. Yes I am able to get 0.7A from a single LT3045 (internal current limiter configured for 695mA) but is it the right way to use it? My 5seater car can easily carry 7PAX, but i dont think that i can sell it as a 7seater van. Even your beautiful LPS-1 (Supercap followed by single TPS7A4700) rated for 1A only, but LPS1.2 (supercap followed by the same TPS7A4700 and dual LT3045) rated for 1.1A. I can not find any logical explanation why the old LPS-1 is rated for 1A only...
  4. Alex, as per LT3045 specs it is 1A MAX, probably you can send an email to Analog devices and ask to revise the specs as per your measurements and about the current limit, can you confirm how many ampers can be provided with 215Ohm ILIM resistor (and it is not 0.55A per IC)
  5. Hi Rajiv You are right - driving/feeder is important for any PSU, even Uptone LPS-1.2 is sensitive for the feeder type. Several users confirm that its works better with a Linear PSU as a feeder vs stock Meanwell SMPS (in therory it should not make a difference because the dual stage linear regulator of lps1.2 is powered by isolated supercap bank/and not by the drive/feeder PSU). It might be interesting if someone can make a direct comparison of cheap Linear PSU (like STUDER900 15W Regulated PSU) followed by DXP-1A5DSC vs Uptone LPS-1.2 with stock SMPS Again - it is true, tripple LT3045 can provide 1.5A max (and dual LT3045, like LPS1.2 - 1A only and not 1.1A, @Superdad confirms that LPS1.2 can provide 1.1A, but accordind to the regulators specs TPS7A4700 and dual LT3045 used in LPS1.2 is rated for 1A only and higher rating is purely marketing, internal LT3045 current limiter configured for 0.7A, so dual lt can provide 1.4A and triple LT3045 upto 2.1A, but can not provide listed specs for the noise and PSRR it is abit complex, all internal parts of DXP are rated for 100C+ operation (125C for LT3045, X7R MLCC and Tantalum caps are rated for 125C, Polymer Caps for 105C), 3W per stage is a safe margin, but with 6W of dissipated power the chassis temperature can reach 70C+ and 6W per stage can burn the internal parts and might require expensive repairing (like 1$ parts replacing) you can not parallel LPS1/1.2, but can parallel 2xLT3045A LDOVR boards and feed them with 2 LPS PSU independently
  6. i am apologies for the delays, but i can start shipments by the last week of January only , i can not get enclosures faster, Chrismass and New Year holidays affecting deliveries
  7. Hi I have limited abilities to comment here due to my internet access limitation. Please note that above calculations valid only for the "measurements were taken in still air on a 4 layer FR-4 board with 1oz solid internal planes and 2oz top/bottom planes with a total board thickness of 1.6mm. The four layers were electrically isolated with no thermal vias present." but not valid for dxp Very efficient heatsink enclosure (7.32C/W), Copper Heatbridge with thermal trasnfer tapes 10x35x5mm (<2C/W), Unique Thermal Vias Pattern and PCB Layout, all this allow you to have upto 4W dissipated power for single stage and up to 6W for dual stage PSU (with equal heat dissipation for each board). By other word it is safe to feed 5VDC out single stage even with 9VDC in if output current do not exceed 1A
  8. does my topic violates any of CA rules? and it is reffered to @Superdad comments about 4xLT3045 chineese board here (does is looks like "talk about competitors or competitor's products" or "sneaky sentence" in your opinion? ) and few following comments with my name as an opponent comment one comment two
  9. Thank you for the information, I add company details in my profile as requested, but I think most of the CA members can identify me by email. Is there any place I can read about the rules for industry member's limitations and forbidden subjects
  10. Yes, but i am not going to promote it here. May I ask why did you ask such a question?
  11. 1. I am not a professional radio engineer 2. English is not my native language I don’t agree with @Superdad that ILIM based “unique” way of paralleling LT3045 is better and this is the only reason why I don’t use it. I already explained why the statement about his “way to cut the output impedance nearly in half” is a bit tricky (because it is very low absolute values and a minor part of the full impedance measured at the point of load even with high quality cable/connectors used). And don’t forget - the maximum power transfer from a source to a load is usually achieved when the load impedance matches the source impedance. Let’s focus on the second part of why I think it is harmful. Let’s check block diagram below, and see how current monitor circuit can impact overall performance. with a classic design (without ILIM compensation), reference voltage (SET PIN) is a function of the current sourced by VERY HIGH QUALITY CURRENT REFERENCE (100uA) followed by a single resistor Rset and Cset capacitor in parallel with Rset (Green path). Vout=Vref = Iref*Rset And this layout can provide precise reference voltage for the regulator circuit. As you can see there is no gain from the SET pin to the output which means any noise that appears on the reference circuit will not be multiplied (like for the conventional linear regulators with ref voltage and resistor divider). Another picture (Red trace) – if you add ILIM circuit, which is designed for output current limitation/monitoring. It is a bit tricky to use it for the drop compensation, but to simplify let’s assume that ILIM circuit is just adding compensation voltage to the reference point. Actually Vref = Iref *(Rset +Rcdc) + Iout/500*Rcdc Points that I am aware of 1. Unlike from the HIGH QUALYTY Current 100uA reference source, ILIM circuit (not a constant but the function of output current) can inject unwanted noise into the reference point, any noise that appears on the reference circuit will hit at the output as well. 2. ILIM feedback (drop compensation voltage) will not appear at the SET PIN immediately, still we need time to charge/discharge Cset Capacitor, with capacity relatively high (few uF) and charging current very low (100uA), and discharge via few KOhm resistor. All this will cause significant delay in action and in some cases such compensation can make things even worse. I will appreciate any comment from skilled professionals, especially @Superdad and @JohnSwenson Best regards Alex
  12. i will be happy to discussi it with @Superdad but very often he is ingoring my questions i really want to know more details about measurements they did, see diagramms available if any, equipment used for the measurements etc
  13. Again, In my humble opinion, ILIM drop compensation is USELESS... I have only following statements from @Superdad 1. Output impedance for LPS 1.2 is a "FEW" mOhms 2. ILIM Circuit is a “easy way to cut the output impedance nearly in half” So – what is the “few mOhms” in figures??? Should I consider it as 10mOhm with ILIM? And <20mOhm without ILIM? You need to add also 2 connectors and feeder cable resistance and easily can have additional 50-100mOhms impedance at the point of load - difference will be 50 vs 60mOhms or even 100 vs 110mOhms between ILIM/No ILIM options.
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