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Anker PowerPort Speed 5 12v DC Conversion

A few months ago I did a teardown on this Anker PowerPort Speed 5 USB charger, but I didn’t get round to detailing the conversion to 12v I had to do, so I’ll get to that now I’ve got a couple more to convert over.

Power Module
Power Module

Here’s the internals of the Anker charger once I’ve removed the casing – which like many things these days, is glued together. (Joints can be cracked with a screwdriver handle without damaging the case). There’s lots of heatsinking in here to cool the primary side switching devices & the pot core transformers, so this is the first thing to get removed.

Heatsink Removed
Heatsink Removed

Once the heatsink has been removed, the pot core transformers are visible, wrapped in yellow tape. There’s some more heatsink pads & thermal grease here, to conduct heat better. The transformers, primary side switching components & input filter capacitor have to go.

Primary Side Components Removed
Primary Side Components Removed

Here’s the PCB once all the now redundant mains conversion components have been deleted. I’ve left the input filtering & bridge rectifier in place, as this solves the issue of the figure-8 cable on the input being reversible, polarity of the input doesn’t matter with the bridge. I’ve removed the main filter capacitor to make enough room for the DC-DC converters to be fitted.

Tails Installed
Tails Installed

Installing the tails to connect everything together is the next step, this charger requires two power supplies – the QC3 circuits need 14.4v to supply the multi-voltage modules, the remaining 3 standard ports require 5v. The DC input tails are soldered into place where the main filter capacitor was, while the outputs are fitted to the spot the transformer secondary windings ended up. I’ve left the factory Schottky rectifiers in place on the secondary side to make things a little more simple, the output voltages of both the DC-DC converters does need to be increased slightly to compensate for the diode drops though. I’ve also bypassed the mains input fuse, as at 12v the input current is going to be substantially higher than when used on mains voltage.

DC-DC Converters Installed
DC-DC Converters Installed

With a squeeze both the boost converter & the buck converter fit into place on the PCB.

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Sony PS3 APS-227 Power Supply Voltage Mod

Specifications

After I did the voltage mod on the APS-231 PSU power supply, I did some reading online & discovered there’s a more powerful PS3 supply – the APS-227. This beast has a 32A +12v rail, with a 3A +5v standby rail.

Specifications
Specifications

As far as I can tell, these are used in another version of the PS3, obviously with a chunkier requirement for 12v DC.

DC Output
DC Output

The main DC rail appears through the same type of connector as the smaller supply, which is compatible with  standard banana plugs.

HV DC Bus Capacitors
HV DC Bus Capacitors

These PSUs are very high build quality, Nichcon electrolytics are used all over the place. These are the HV DC rail filter caps, rated at 100µF 420v.

Output Synchronous FETs
Output Synchronous FETs

Synchronous rectification is also used in these supplies, keeping the waste heat down to a minimum on the output rectification. There’s a thermistor on the heatsink to the left for the thermal protection.

+12v Rail Load Resistors
+12v Rail Load Resistors

A couple of 2.2Ω resistors in series provide a minimum load to the PSU to keep things stable at low power. Adjusting the output too high will likely cause these resistors to overheat.

Transformer
Transformer

The main transformer has a huge secondary winding, only 4 turns of Litz type wire, about 5mm².

Regulator Section
Regulator Section

Here’s the point where the mod needs to be done – the same as the other PS3 supply, a single resistor needs changing for a potentiometer, it’s the 1KΩ one in the center of the photo. (White “102” text on the top, unlike the others which are yellow). Desolder this 0402 resistor.

Mod Wires
Mod Wires

After the resistor is removed, solder the mod wires to these test points.

Mod Pot
Mod Pot

Just like the APS-231, a 1KΩ 18-turn potentiometer is used to tweak the voltage. I’ve secured it with a drop of CA glue to the top of the standby transformer.

OVP Optocoupler Disconnected
OVP Optocoupler Disconnected

The overvoltage protection on this supply is a little more aggressive – tripping things out at 13.4v. However it’s easy to defeat this on this particular supply, by disconnecting the “12V OVP” optocoupler from the secondary side. This does leave the supply with no active overvoltage protection, so be careful on how far the voltage gets tweaked up! The output electrolytics are rated at 16v, so there’s the potential for ballistic capacitors if things are tweaked too far!

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Sony PS3 APS-231 Power Supply Voltage Mod

PSU Ratings
PSU Ratings
PSU Ratings

I was recently given a Sony PS3 with a dead disc drive, and since I’m not a console gamer I figured I’d see if there were any handy parts inside. Turns out these units contain a rather nice SMPS, the Sony APS-231 with a high power 12v rail, rated at 23.5A. A bit of searching around discovered a thread on the BadCaps Forums about voltage modding these supplies for a 13.8v output, suitable for my Ham radio gear.
These supplies are controlled by a Sony CXA8038A, for which there is very little information. Active PFC is included, along with synchronous rectification which increases the efficiency of the supply, and in turn, reduces the waste heat output from the rectifiers.

Regulation Section
Regulation Section

Like many of the SMPS units I’ve seen, the output voltage is controlled by referencing it to an adjustable shunt reference, and adjusting the set point of this reference will in turn adjust the output voltage of the supply, this is done in circuit by a single resistor.

Here’s the regulator section of the PSU, with the resistors labelled. The one we’re after changing is the 800Ω one between pins 2 & 3 of the TS2431 shunt reference. It’s a very small 0402 size resistor, located right next to the filter electrolytic for the 5v standby supply circuit. A fine tip on the soldering iron is required to get this resistor removed.

Attachment Points
Attachment Points

Once this resistor is removed from the circuit, a 1KΩ 18-turn potentiometer is fitted in it’s place, from the Anode (Pin 3) to the Ref. (Pin 2) pins of the TS2431 shunt reference. I initally set the potentiometer to be the same 800Ω as the factory set resistor, to make sure the supply would start up at a sensible voltage before I did the adjustment.

Potentiometer
Potentiometer

The pot is secured to the top of the standby supply transformer with a drop of CA glue to stop everything moving around. The supply can now be adjusted to a higher setpoint voltage – 13.8v is about the maxumum, as the OVP cuts the supply out at between 13.9v-14v.

Modded Voltage
Modded Voltage

After doing some testing at roughly 50% of the supply’s rated load, everything seems to be stable, and nothing is heating up more than I’d expect.