Attempts at reading parallel NAND Flash with Arduino

NAND Flash chips are widely used non-volatile memory devices. They have high storage capacity, fast access time and are reliable, usually being able to withstand 100,000 erase/program cycles. Such chips are available with parallel or serial interface (commonly SPI). While the latter can be easily interfaced to any SPI port and can be read/programmed even by slow microcontrollers, parallel chips are faster and require more data lines (connections) to host microcontroller.

Having an old DSL modem which cannot be flashed with a locked bootloader and unavailable JTAG port I unsoldered its NAND flash. I do not own a parallel memory programmer and I do not intend to buy one for the sole purpose of dumping useless data from this flash. So, I attempted to interface this memory to what I have. At first it seemed it has too many pins to wire it to a common ATmega328p Arduino. But the datasheet revealed something else.

USB Power Supply for Breadboard

Breadboards are very useful for quickly building electronic circuits. But these circuits require power. The popular breadboard power supply you will find on the market is powered from more than 8 V by an AC-DC adapter. They can provide both 5V and 3.3V from linear 1117 regulators. These regulators can supply a maximum of 800mA, but because they work in linear mode and the PCB is not well built for heat dissipation, the current you can draw from such a device is very limited.

While trying to interface a gas sensor and a TV card tuner to an Arduino, I found that I had troubles powering them. Each of the mentioned devices need about 200mA. Both Arduino and the breadboard power supply use linear voltage regulators to provide 5V. I tried to use the breadboard power supply, but the regulator became hot immediately. Being fed with 12V, the 1117 regulator needed to dissipate (12 - 5) x 0.2 = 1.4 W. That's a lot for its small package.

I needed a better power supply. And I want it for breadboard projects. USB seems to be a pretty good power source, being able to provide at least 500mA. So I designed my own power supply. Since is USB powered, I thought it would be a good idea to have an USB port where I could plug development boards, without needing another computer USB port.