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Dyson DC16 Handheld Teardown

DC16
DC16

The Dyson DC16 is one of the older handheld vacuums, before the introduction of the “Digital Motor”. (Marketing obviously didn’t think “Switched Reluctance Motor” sounded quite as good).

These vacuums have a very large DC brush motor driving the suction turbine instead, the same as would be found in a cordless power tool.

Control PCB
Control PCB

Popping the front cap off with the ID label, reveals the brains of the vacuum. The two large terminals at the right are for charging, which is only done at 550mA (0.5C). There are two PIC microcontrollers in here, along with a large choke, DC-DC converter for supplying the logic most likely. The larger of the MCUs, a PIC16HV785, is probably doing the soft-start PWM on the main motor, the smaller of the two, a PIC16F684 I’m sure is doing battery charging & power management. The motor has a PCB on it’s tail end, with a very large MOSFET, a pair of heavy leads connect directly from the battery connector to the motor.
Just out of sight on the bottom left edge of the board is a Hall Effect Sensor, this detects the presence of the filter by means of a small magnet, the vacuum will not start without a filter fitted.

Battery Pack
Battery Pack

The battery pack is a large custom job, obviously. 4 terminals mean there’s slightly more in here than just the cells.

Battery Cracked
Battery Cracked

Luckily, instead of ultrasonic or solvent welding the case, these Dyson batteries are just snapped together. Some mild attack with a pair of screwdrivers allows the end cap to be removed with minimal damage.

Cells
Cells

The cells were lightly hot-glued into the shell, but that can easily be solved with a drop of Isopropanol to dissolve the glue bond. The pack itself is made up of 6 Sony US18650VT High-Drain 18650 Li-Ion cells in series for 21.6v nominal. These are rated at a max of 20A discharge current, 10A charge current, and 1.3Ah capacity nominal.
There’s no intelligence in this battery pack, the extra pair of terminals are for a thermistor, so the PIC in the main body knows what temperature the pack is at – it certainly gets warm while in use due to the high current draw.

Motor
Motor

Hidden in the back side of the main body is the motor. Unfortunately I wasn’t able to get this out without doing some damage, as the wiring isn’t long enough to free the unit without some surgery.

Turbine
Turbine

The suction is generated by a smaller version of the centrifugal high-speed blowers used in full size vacuums. Not much to see here.

Unofficial Charger
Unofficial Charger

Since I got this without a charger, I had to improvise. The factory power supply is just a 28v power brick, all the charging logic is in the vacuum itself, so I didn’t have to worry about such nasties as over-charging. I have since fitted the battery pack with a standard Li-Po balance cable, so it can be used with my ProCell charger, which will charge the pack in 35 minutes, instead of the 3 hours of the original charger.

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Mini Teardown: Eberspacher 701 BT Controller

It’s well known that there are two versions of the 701 type controller available for Eberspacher heaters, the version with the blue logo is the official un-restricted model, while the version with the white logo is a version built for BT that restricts the heater to 1 hour runtime & has no diagnostics built in.
As these devices are microcontroller driven, I assumed that the hardware would be the same, only the code running in the micro being the bit that Eberspacher changed. This option would certainly have been the lowest cost.

Controller PCB Rear
Controller PCB Rear

Here’s the PCB removed from the plastic housing. There are definitely some differences that I can tell. As the un-restricted version has an extra wire for the diagnostic serial interface, and this board has no unpopulated parts, the PCB is definitely a different version.
In the centre is a Microchip PIC16C622 microcontroller, the OTP version in this case for cost reductions. (I may try reading the binary from this chip in the future, chances are it’s code protected though).
Below the micro is an NXP PCF8577C 32-segment LCD controller, this has an I²C interface to the PIC.
The temperature control function on these heaters is done via applying a resistance to one of the control lines, between 1750Ω-2180Ω, ±80Ω. (Very odd values these, not to mention no standard components can create this range easily, bloody engineers >_<). This is accomplished in hardware with a BU2092F I²C shift register from Rohm, which is connected to a bank of resistors. The microcontroller will switch combinations of these into the circuit to get the range of resistances required.
The rest of the circuit is local power regulation & filtering.

Controller PCB Front
Controller PCB Front

There’s not much on the other side of the PCB, just the LCD itself & the contacts for the buttons.

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Belkin 2 Port KVM Switch

Main Body
Main Body

Here is an old type KVM switch, PS/2 & VGA interface.

Label
Label

Details Label

Top Removed
Top Removed

Top removed from the main body, the cables coming in from the bottom connect to the VGA, keyboard & mouse ports on the slave computers, the connectors at the top connect to the single monitor, keyboard & mouse.

PCB
PCB

PCB removed from the body. This is driven by a PIC16C57C-04 microcontroller.
The pair of LEDs indicate which computer is using the peripherals at any one time.