September 2010 – Experimental Engineering

Posted on September 23, 2010 by The Engineer — Leave a comment

Belkin F5U021 4-Port USB Hub

This is an old USB 1.1 hub that was recently retired from service on some servers. Top of the unit visible here.

Bottom label shows that this is a model F5U021 hub, a rather old unit.

PCB is here removed from the casing, Indicator LEDs along the bottom edge of the board, power supply is on the left. Connectors on the top edge are external power, USB host, & the 4 USB outputs. Yellow devices are polyswitch fuses for the 500mA at 5v each port must supply.

This is the USB Hub Controller IC, which is a Texas Instruments TUSB2046B device. Power filter capacitors next to the USB ports are visible here also, along with 2 of the polyswitches.

The power supply section of the unit, which supplies regulated 5v to the ports, while supplying regulated 3.3v to the hub controller IC. Large TO-220 IC is the 5v regulator. Smaller IC just under the power selector switch is the 3.3v regulator for the hub IC. The switch selects between Host powered or external power for the hub.

Posted on September 23, 2010 by The Engineer — Leave a comment

USB Flash Drive

Here is a cheap chinese made flash drive given out for free by Westlaw UK. Capacity 512MB

Here is the PCB removed from the casing, USB connector on the left, followed by the clock crystal for the flash controller, a CBM2092, which is a Chipsbank part. 512MB flash memory IC, unknown maker. Access LED on far right of the board.

Posted on September 22, 2010 by The Engineer — 2 Comments

Epson Ink Cartridge Resetter

This is a device designed to reset Epson brand ink cartridges that are reportedly out of ink, so they again report full to the printer Here is the front of the unit, with the guide for attaching to a cartridge.

Back of the device removed. 3 button cells provide power to the PCB. Indicator LED sticks out of the top of the device for reset confirmation.
Row of pads on far left edge of the PCB are presumably a programming header for the uC on the other side of the board.

Here is the front of the PCB, main feature being the grid of pogo pins to connect to the cartridge chip. IC on lower right of that is a MSP430F2131 uController, a Texas Instruments part.
The IC directly to the left of the pogo pin bed is a voltage regulator, to step down the ~4.5v of the batteries down to the ~3.3v that the uC requires.