Reverse engineering of BK Precision 1696 switching power supply’s LCD protocol

Kerry Wong writes: As mentioned in my previous post, besides the broken LCD there was also an issue with the power supply portion of the unit and the output voltage was clamped at around 10 to 11V. The digital circuitry portion however seemed to be intact. Unfortunately since an identical LCD is virtually unobtanium, I […]

Examining a vintage RAM chip, I find a counterfeit with an entirely different die inside

Ken Shirriff writes, “A die photo of a vintage 64-bit TTL RAM chip came up on Twitter recently, but the more I examined the photo the more puzzled I became. The chip didn’t look at all like a RAM chip or even a TTL chip, and in fact appeared partially analog. By studying the chip’s […]

Nuclear physic applied in smoke detectors

Robert Gawron writes: Not many people know, but in some smoke detectors, radioactive materials play an essential role. Today I will present one of those devices, and my -successful- attempt to reverse engineer it and get the circuit diagram. Those smoke detectors uses a small amount of Americium-241 (chemical symbol: Am) obtained in nuclear reactors […]

Reverse engineering the popular 555 timer chip (CMOS version)

Ken Shirriff wrote an article on reverse engineering a 555 timer chip,  He writes: This article explains how the LMC555 timer chip works, from the tiny transistors and resistors on the silicon chip, to the functional units such as comparators and current mirrors that make it work. The popular 555 timer integrated circuit is said to be […]

More ARM1 processor reverse engineering: the priority encoder

In a previous post, Ken Shirriff reverse engineered the silicon in the ARM1 processor, this time he reverse-engineer the priority encoder in the ARM1 processor: In this article, I reverse-engineer the priority encoder in the ARM1 processor. By examining the chip layout provided by the Visual ARM1 project, I have determined how this circuit works […]

Kit assembly 0-30V 0-3A adjustable linear power supply

Florin of YourITronics writes, “In this video I am assembling a 0-30V 0-3A Adjustable Linear Power Supply kit. Will it work at first power on? Or will Murphy get me this time? Watch the video and see how I got myself into trouble. I also reverse engineered and got a schematic of this kit which I […]

Reverse engineer wireless temperature / humidity / rain sensors, part 1

Ray Wang writes: I just wrote a series of three posts about how I reverse engineered a few off-the-shelf wireless temperature, humidity sensors and rain gauge, and used an Arduino to listen to and decode the sensor data. The tools involved are quite simple: an Arduino and a 433MHz RF receiver. I also used a […]