Creative Woofer SBS 2.1 370 power supply

Preamble

I had the chance to get a Creative woofer SBS 2.1 370 for 40 baht, but it was missing a power supply: 11.5V 1.6A. Not a common supply, and I wondered if a 12V 2A would suffice, or whether the higher voltage would damage the unit

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Burnt out USB charger

Preamble

It’s one of those horrifically dangerous 2.5×2.5×2.5 cm mini-cube singe port 1 A USB chargers. There were scorch marks on the base of the case. The circuit was very simple, a simplified SMPS on two small PCBs… which held into the cube casing with white silicone/glue – scratch that away and it is easy to extract the pair of PCBs

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High power USB charging station

Preamble

Whilst looking into the XTAR battery chargers, I came across the XTAR EU4, which offers QC3.0, 2 x USB 2.4A and USB C (PD) ports… and although the QC and PD capability is a bit limited, it’s not by much (i.e. QC 3.0 does not have 20V capability, and PD current is limited to 20V 2.25A (45W))…

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Is the XTAR product department confused?

Preamble

XTAR… Due to my unfortunate experience with the awful charging functionality of a Wismec RX200 vaper, I was looking into getting a upgrade to my agéd yet venerable XTAR VC2 (which was able to resurrect a dead LiPo, see Reviving a dead 18650 LiPo) and I was perusing the XTAR Official Store on AliExpress. Now, while the newer products are all really rather good, there seem to be some inconsistencies between the XTAR product range and the naming.

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Synth Power Supplies

Preamble

Sort of following on from VCO madness, I was really looking for the Super Simple VCO (which seems to be actually a 555 timer as a VCO, see the GetLoFi LFO in Ha Ha Ha… 555 fun). However, I got distracted and ended up analysing PSUs and buses for synths.

For ease, in order to power my synth, I had been planning on using a couple of single rail 12V SMPS designed for LED lights, in order to make a dual rail supply, but I started to wonder about the noise implications – as all designs for synths appear to use the old fashioned transformer, rectifier, and linear regulator approach.

(As an aside, Julien Ilett also points this potential noise (as related to buck convertors and SMPS) issue out in Julian builds: a Split Voltage Power Supply (+/-12v and 5v) @5:20. See also, Julian’s Postbag: #85 – E.Ink, Spring Onion, Split PSU (@7:33-8:00), where he mentions that high frequency noise is not removed by the linear regulators in the Split Rail Power Supply Kit Build – SEPIC Cuk Topology).

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