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PowerAdd Pilot X7 20,000mAh Powerbank & Fast Charging Mod

PowerAdd Pilot X7
PowerAdd Pilot X7

Here’s the biggest portable USB powerbank I’ve seen yet – the PowerAdd Pilot X7, this comes with a 20Ah (20,000mAh) capacity. This pack is pretty heavy, but this isn’t surprising considering the capacity.

USB Ports & LED
USB Ports & LED

The front of the pack houses the usual USB ports, in this case rated at 3.4A total between the ports. There’s a white LED in the centre as a small torch, activated by double-clicking the button. A single click of the button lights up the 4 blue LEDs under the housing that indicate remaining battery capacity. Factory charging is via a standard µUSB connector in the side, at a maximum of 2A.

PCB Front
PCB Front

The front of the PCB holds the USB ports, along with most of the main control circuitry. At top left is a string of FS8025A dual-MOSFETs all in parallel for a current carrying capacity of 15A total, to the right of these is the ubiquitous DW01 Lithium-Ion protection IC. These 4 components make up the battery protection – stopping both an overcharge & overdischarge. The larger IC below is an EG1501 multi-purpose power controller.

This chip is doing all of the heavy lifting in this power pack, dealing with all the DC-DC conversion for the USB ports, charge control of the battery pack, controlling the battery level indicator LEDs & controlling the torch LED in the centre.

EG1501 Example
EG1501 Example

The datasheet is in Chinese, but it does have an example application circuit, which is very similar to the circuitry used in this powerbank. A toroidal inductor is nestled next to the right-hand USB port for the DC-DC converter, and the remaining IC next to it is a CW3004 Dual-Channel USB Charging Controller, which automatically sets the data pins on the USB ports to the correct levels to ensure high-current charging of the devices plugged in. This IC replaces the resistors R3-R6 in the schematic above.
The DC-DC converter section of the power chain is designed with high efficiency in mind, not using any diodes, but synchronous rectification instead.

PCB Back
PCB Back

The back of the PCB just has a few discrete transistors, the user interface button, and a small SO8 IC with no markings at all. I’m going to assume this is a generic microcontroller, (U2 in the schematic) & is just there to interface the user button to the power controller via I²C.

Cells
Cells

Not many markings on the cells indicating their capacity, but a full discharge test at 4A gave me a resulting capacity of 21Ah – slightly above the nameplate rating. There are two cells in here in parallel, ~10Ah capacity each.

XT60 Battery Connector
XT60 Battery Connector

The only issue with powerbanks this large is the amount of time they require to recharge themselves – at this unit’s maximum of 2A through the µUSB port, it’s about 22 hours! Here I’ve fitted an XT60 connector, to interface to my Turnigy Accucell 6 charger, increasing the charging current capacity to 6A, and reducing the full-charge time to 7 hours. This splits to 3A charge per cell, and after some testing the cells don’t seem to mind this higher charging current.

Battery Connector Wiring
Battery Connector Wiring

The new charging connector is directly connected to the battery at the control PCB, there’s just enough room to get a pair of wires down the casing over the cells.

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Anker PowerPort Speed 5 USB Rapid Charger Teardown

Front
Front

Here’s a piece of tech that is growing all the more important in recent times, with devices with huge battery capacities, a quick charger. This unit supports Qualcomm’s Quick Charge 3 standard, where the device being charged can negotiate with the charger for a higher-power link, by increasing the bus voltage past the usual 5v.

Rear
Rear

The casing feels rather nice on this unit, sturdy & well designed. All the legends on the case are laser marked, apart from the front side logo which is part of the injection moulding.

Specifications
Specifications

The power capacity of this charger is pretty impressive, with outputs for QC3 from 3.6-6.5v at 3A, up to 12v 1.5A. Standard USB charging is limited at 4.8A for the other 3 ports.

Ports
Ports

The two of the 5 USB ports are colour coded blue on the QC3 ports. The other 3 are standard 5v ports, the only thing that doesn’t make sense in the ratings is the overall current rating of the 5v supply (4.8A), and the rated current of each of the ports (2.4A) – this is 7.2A total rather than 4.8A.

Top Removed
Top Removed

The casing is glued together at the seam, but it gave in to some percussive attack with a screwdriver handle. The inside of this supply is mostly hidden by the large heatspreader on the top.

Main PCB Bottom
Main PCB Bottom

This is a nicely designed board, the creepage distances are at least 8mm between the primary & secondary sides, the bottom also has a conformal coating, with extra silicone around the primary-side switching transistor pins, presumably to decrease the chances of the board flashing over between the close pins.
On the lower 3 USB ports can be seen the 3 SOT-23 USB charge control ICs. These are probably similar to the Texas Instruments TPS2514 controllers, which I’ve experimented with before, however I can’t read the numbers due to the conformal coating. The other semiconductors on this side of the board are part of the voltage feedback circuits for the SMPS. The 5v supply optocoupler is in the centre bottom of the board.

Heatsink Removed
Heatsink Removed

Desoldering the pair of primary side transistors allowed me to easily remove the heatspreader from the supply. There’s thermal pads & grease over everything to get rid of the heat. Here can be seen there are two transformers, forming completely separate supplies for the standard USB side of things & the QC3 side. Measuring the voltages on the main filter capacitors showed me the difference – the QC3 supply is held at 14.2v, and is managed through other circuits further on in the power chain. There’s plenty of mains filtering on the input, as well as common-mode chokes on the DC outputs before they reach the USB ports.

Quick Charge 3 DC-DC Converters
Quick Charge 3 DC-DC Converters

Here’s where the QC3 magic happens, a small DC-DC buck converter for each of the two ports. The data lines are also connected to these modules, so all the control logic is located on these too. The TO-220 device to the left is the main rectifier.

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3M Microtouch 17″ Raspberry Pi Touch PC

A while back I posted about a 3M Touch Systems industrial monitor that I’d been given. I had previously paired it with a Raspberry Pi Model B+, but for general desktop use it was just a little on the slow side.

Since the release of the Raspberry Pi 2, with it’s 4-core ARM Cortex CPU, things are much improved, so I figured I’d post an update with the latest on the system.

The monitor I’ve used is a commercial one, used in such things as POS terminals, service kiosks, etc. It’s a fairly old unit, but it’s built like a tank.

3M Panel
3M Panel

It’s built around a Samsung LTM170EI-A01 System-On-Panel, these are unusual in that all the control electronics & backlighting are built into the panel itself, instead of requiring an external converter board to take VGA to the required LVDS that LCD panels use for their interface.

The touch section is a 3M Microtouch EXII series controller, with a surface capacitive touch overlay.

Touch Controller
Touch Controller

Above is the touch controller PCB, with it’s USB-Serial converter to interface with the Pi.

As there is much spare space inside the back of this monitor, I have mounted the Pi on a couple of spare screw posts, fitted USB ports where the original VGA & Serial connectors were in the casing, and added voltage regulation to provide the Pi with it’s required 5v.

Overview
Overview

Here’s the entire back of the panel, the Pi in the middle interfaces with a HDMI-VGA adaptor for the monitor, and the serial adaptor on the right for the touch. A small voltage regulator at the bottom of the unit is providing the 5v rail. There’s a switch at the bottom next to one of the USB ports to control power to the Pi itself. The panel won’t detect the resolution properly if they’re both powered on at the same time.

At 13.8v, the device pulls about 2A from the supply, which seems to be typical for a CCFL backlighted LCD.
Now the Raspberry Pi 2 has been released, it’s much more responsive for desktop applications, especially with a slight overclock.

Shameless Plug
Shameless Plug

A full disk image enabled for Desktop & 3M touch monitors is available below for others that have similar panels. This image only works for the Pi 2!

[download id=”5591″]