Today we’ll be taking a look at Plustek OpticSlim M12 Corporate USB Scanner which is a single sheet scanner, powered by USB.
2 screws later and we’re in.
The shell comes apart, we have the small buttons PCB on the top and the scanner and motor on the bottom. A few more screws later and we’ve got to the main PCB.
We have a relatively long PCB that has single chip solution with a motor driver. The scanning element was connected with a flat flex cable. PCB date code is 1st week of 2007 but it’s strange that they have another date code of 2002 on the board, maybe this PCB was part of an older product.
For the power side, the input goes through a 3A fuse and what might be a P or N mosfet at the bottom of the board. There are 2x AMS1117 LDOs, one of them have an inductor with 2x 47uF capacitors before feeding into the main chip. We also have a MC34063 (unknown brand) DC-DC with a large value inductor of 220uH but is standard for using the 34063. There is just 1 logic chip, a 74HC04 hex inverter.
The main chip is the Grandtech GT-6816 which is designed for scanning applications with a 16bit analog front end, CCD/CIS sensor support, 16KB line buffer, USB or parallel port support and it runs at 48MHz with a 6MHz crystal. We have a Microchip 24LC16B 16Kbit I2C EEPROM which the GT-6816 uses to boot from.
The motor driver is an On Semi LB1940, a 2 channel H-Bridge constant current driver which supports a low voltage from 1.9V to 7.5V and it support 400mA output current.
And that’s all.