TheSignalPathBlog @ youtube.com:
In this episode Shahriar attempts a repair of an Agilent E3642A DC Power Supply which is completely non-responsive. After presenting a teardown of the power supply, the GPIB interface is used to verify the functionality of the power supply. The problem is traced to the main display unit which communicated with the main power supply via a serial interface.
After disassembly of the display, it is revealed that the entire unit has suffered a catastrophic failure due to the VFD display drive IC. All components must be individually removed and replaced. Unfortunately the main processor is a Mask ROM IC version (80C51) and cannot be sourced. Can you help Shahriar find a replacement part?
Teardown, Repair and Analysis of an Agilent E3642A DC Power Supply - [Link]
I bought recently on yahoo auctions a set of 4 gameboys (1 brick, 2 colors and 1 pocket 1st gen) because I had a plan to hack them and I needed some guinea pigs. I have already 2 at home but … well, it was a total of 1,500 JPY (10 euro w/ delivery) so. Got them yesterday morning, quick check: all working modulo the inevitable sticky buttons or gunk that went everywhere after 15 years. Dismantle, wash (water & soap), remove glue (ugly pokemon stickers) and marker (acetone), dry, reassemble. Working fine, nice looking and that vomiting man-sweat smell is gone (previous owner must have had very sweaty hands).
Gameboy battery upgrade - [Link]
Jason over at Rip It Apart did a teardown of a Kentli PH5 1.5 V Li-Ion AA battery:
The PCB that holds the 1.5 volt regulator is inside the end cap, with the rest made up of the Li-ion cell itself. Curiously enough, the cell inside is labeled “PE13430 14F16 2.66wh” which is interesting in more than one way. First of all, the rated energy content of the cell is less than what’s on the outside label (2.66 watt-hours versus 2.8), and the cell inside is actually a Li-ion polymer (sometimes called a “Li-Po” cell) type; I was expecting a standard cylindrical cell inside. Unfortunately, my Google-fu was unable to pull up any data on the cell. I might attempt to do a chemistry identification cycle on the cell and see if TI’s battery database can bring something up.
Teardown of Kentli PH5 1.5 V Li-Ion AA battery - [Link]
by Stephen Evanczuk @ digikey.com:
For rapidly growing markets such as wearables or the Internet of Things (IoT), energy harvesting can significantly enhance battery life—or even enable battery-free designs. At the same time, however, engineers designing wearables and IoT devices face significant constraints in total design size and footprint. To meet growing demands for miniaturized systems, designers can turn to an array of highly integrated energy-harvesting ICs and wireless MCUs from silicon vendors including Atmel, CSR, Freescale Semiconductor, Linear Technology, Maxim Integrated, NXP Semiconductor, Silicon Laboratories, STMicroelectronics, and Texas Instruments, among others.
Energy harvesting offers tremendous benefits for applications able to take advantage of ambient-energy sources. Designers have employed energy-harvesting techniques to power applications ranging from motor and engine monitors to railway trackside electronics. Typically, these applications are based on wireless-sensor designs built to transmit sampled data about the environment or events of interest to a controller, aggregator, or other host (Figure 1).
Specialized ICs Squeeze Large Capabilities into Tiny Energy-Harvesting Solutions - [Link]
by Afrotechmods @ youtube.com
A beginner’s guide to different battery chemistries and how to choose the right battery for your project.
How to choose a battery: A battery chemistry tutorial - [Link]
by Solarcycle @ instructables.com:
Power Stacker is a portable, modular, USB rechargeable lithium-ion battery pack. Stack them together for power hungry projects or separate them for smaller projects with this modular system. The Gerber, BOM, and .STL files are available below.
Power Stacker does what other USB rechargeable batteries have failed to do, and that’s the ability to combine together for increased battery capacity or separate in to many small batteries for smaller projects. You can literally use the same Power Stacker batteries for many years across many applications!
Stackable USB Rechargeable Battery System - [Link]
by Jim @ jimlaurwilliams.org:
I got a couple of cheap ($1.29) 1A USB LiPo chargers since I’m doing more and more LiPo/LiIon powered stuff. I mostly discharged a recycled 18650 cell for a test load and it looks like it does charge at nearly 1A. Two LEDs – red charging, green (mine is blue) fully charged. Seems like a pretty ideal cheap device.
Cheap USB LiPo charger notes - [Link]
The Gertbot board works as either a stand-alone power controller connected to a computer via a serial link and controlled from Windows or as a plug-in to the Raspberry Pi environment. It has four channels each capable of driving 30 V at 2.5 A and can drive both capacitive and inductive loads. Besides four H-bridges the board also has two open drain N-MOSFETS which can sink 3 A at 30 V. The board is primarily targeted to drive stepper motors, brushed motors and other robotic hardware but it will be just as much at home controlling power in other applications. The outputs have short-circuit and thermal protection.
The Gertbot Power Controller - [Link]
By Steven Keeping @ digikey.com:
Switching DC-DC voltage converters (“switching regulators”) offer some key advantages over linear regulators. Chief among these are efficiency and flexibility; switching regulators can step-up (boost), step-down (buck), and invert voltages with ease. Contemporary modular chips are compact, reliable, and available from multiple suppliers (see the TechZone article “Understanding the Advantages and Disadvantages of Linear Regulators” for a full comparison between switching and linear regulators).
However, this flexibility comes at the expense of increased complexity. For an engineer familiar with the elegance of a linear regulator, designing a power supply based around a switching device can be a little daunting. The key to overcoming the challenge is an understanding of what is going on inside that little black chip.
The Difference Between Switching Regulator Continuous and Discontinuous Modes - [Link]
A battery charger is a device used to energize a rechargeable battery by driving an electric current through it. The charging protocol depends on the size and type of the battery being charged. Some battery types have high tolerance for overcharging and can be recharged by connection to a constant voltage source or a constant current source; simple chargers of this type require manual disconnection at the end of the charge cycle, or may have a timer to cut off charging current at a fixed time.
The MCP1631HV multi-chemistry reference design board is used to charge one, two, three or four NiMH batteries or one or two cell Li-Ion batteries. The board uses the MCP1631HV high speed analog PWM and PIC16F883 to generate the charge algorithm for NiMH, NiCd or Li-Ion batteries. It is used to evaluate Microchip’s MCP1631HV in a SEPIC power converter application. As provided, it is user programmable using on board pushes buttons. The board can charge NiMH, NiCd or Li-Ion batteries. It provides a constant current charge (Ni based chemistry) and constant current / constant voltage (Li-Ion) with preconditioning, cell temperature monitoring (Ni based) and battery pack fault monitoring. Also, the charger provides a status or fault indication. It automatically detects the insertion or removal of a battery pack.
The MCP1631 multi-chemistry battery charger reference design is a complete stand-alone constant current battery charger for NiMH, NiCd or Li-Ion battery packs. When charging NiMH or NiCd batteries the reference design is capable of charging one, two, three or four batteries connected in series. If Li-Ion chemistry is selected, the board is capable of charging one or two series batteries. This board utilizes Microchip’s MCP1631HV (high-speed PIC® MCU PWM TSSOP-20). The input voltage range for the demo board is 5.3V to 16V.
Multi-Chemistry Battery Charger from Microchip - [Link]