by Francesco Truzzi @ b.truzzi.me:
I needed a small, fast and reliable multi-voltage level translator (mainly for connecting ESP8266 boards to the Arduino, got tired of resistor networks pretty quickly) so I built a breakout board for TI’s LSF0204(D).
Datasheet and info here.
The LSF0204 is a nice little chip. It can translate up to 4 signals to and from the following values:
1.0 V ↔ 1.8/2.5/3.3/5 V.
1.2 V ↔ 1.8/2.5/3.3/5 V.
1.8 V ↔ 2.5/3.3/5 V.
2.5 V ↔ 3.3/5 V.
3.3 V ↔ 5 V.
LSF0204 breakout board: a bidirectional, multi-voltage level converter – [Link]
R. Colin Johnson @ eetimes.com:
PORTLAND, Ore. — Complementary metal oxide semiconductor (CMOS) imaging chips are becoming the industry’s leader in advanced process technology — instead of the traditional leaders (processors and memory) — thanks to strong demand for CMOS imaging chips in everything from smartphones to tablets to medical equipment and automobiles. Apparently, now the innovation surpasses Moore’s Law, says analyst firm Yole Développement.
Imaging was once done by film, but with the advent of solid-state sensors the technology breakthroughs seem to be growing exponentially, doubling with each new innovation (see slide 1), thus surpassing the traditional interpretation of Moore’s Law, argues Yole Développement (Lyon, France) in a new paper. Yole calls this effect “More than Moore.”
CMOS Image Sensors Surpassing Moore’s Law – [Link]
This evaluation board has been developed for ROHM’s H-Bridge driver customers evaluating the BD62x2FP series. The BD62x2FP series can operate across a wide range of power supply voltages (from 3V to 32V max), supporting output currents of up to 2A. PWM signal control (20 kHz-100 kHz) or VREF control modes are used to vary motor rotation speeds. ROHM’s ICs are complete with over current protection (OCP), over voltage protection (OVP), thermal shutdown (TSD) and under voltage lock-out (UVLO) protection circuits while also facilitating a low-power consumption design (10μA max).
Rohm H-Bridge Evaluation Board – [Link]
by Vladimir Rentyuk @ edn.com
Suppose that you need to test a 1.5V, AA-size alkaline battery. You can apply a short circuit and measure current, or you can measure open-circuit voltage, but neither method properly tests the battery. A suitable test current of approximately 250 mA gives you a more reasonable test. You can use a 6Ω resistive load at 1.5V, which produces an output voltage of 1.46V at an ambient temperature of 25°C if the battery is in excellent condition. A poor battery might produce less than 1.2V. Given the load, the output current at 1.2V will be 200 mA instead of 250 mA. The battery will have just 80% of a full load current. Instead, you can use the circuit in Figure 1 to produce a constant-current load.
Circuit provides constant-current load for testing batteries – [Link]
by Paul Galluzzi @ edn.com:
The Fig 1 circuit uses a Hall-effect sensor, consisting of an IC that resides in a small gap in a flux-collector toroid, to measure dc current in the range of 0 to 40A. You wrap the current-carrying wire through the toroid; the Hall voltage VH is then linearly proportional to the current (I). The current drain from VB is less than 30 mA.
To monitor an automobile alternator’s output current, for example, connect the car’s battery between the circuit’s VB terminal and ground, and wrap one turn of wire through the toroid. (Or, you could wrap 10 turns—if they’d fit—to measure 1A full scale.) When I=0V, the current sensor’s (CS1’s) VH output equals one-half of its 10V bias voltage. Because regulators IC1 and IC2 provide a bipolar bias voltage, VH and VOUT are zero when I is zero; you can then adjust the output gain and offset to scale VOUT at 1V per 10A.
Current monitor uses Hall sensor – [Link]
Helge @ WeatherStation writes:
After some help from wolfmanjm and CosR1, I managed to get a separate Buydisplay based GSL1680 touch panel up’n running on an Arduino Mega (1280) with only minor modifications to wolfmanjms code.
The firmware is an integrated part of the sketch. Instead of using ram, it is put in the flash memory using PROGMEM. Some, to me, special memory magic is used to read the firmware from the sketch flash (Thanks to CosR1). There might be other ways, but I haven’t investigated further. From there it is easy to write the firmware to the GSL1680 though the I2C bus. Initialization of the GSL1680 is also a bit special. It needs some special sequence of operations. I’m not sure if the code is optimal in that regard, but it seems to be stable. Linux-sunxi.org has a wiki with some info. There is even some information on the internal firmware registers here (haven’t verified if this info is correct).
I’ve forked the original wolfmanjm/GSL1680 github repo to hellange/GSL1680 and checked in the modifications needed for Arduino MEGA.
5″ capacitive touch panel with GSL1680 up’n running with Arduino – [Link]
by deba168 @ instructables.com:
Welcome to my solar charge controller tutorials series.I have posted two version of my PWM charge controller.If you are new to this please refer my earlier tutorial for understanding the basics of charge controller.
This instructable will cover a project build for a Arduino based Solar MPPT charge controller.
Now a days the most advance solar charge controller available in the market is Maximum Power Point Tracking (MPPT).The MPPT controller is more sophisticated and more expensive.It has several advantages over the earlier charge controller.It is 30 to 40 % more efficient at low temperature.
But making a MPPT charge controller is little bit complex in compare to PWM charge controller.It require some basic knowledge of power electronics. I put a lot of effort to make it simple, so that any one can understand it easily.If you are aware about the basics of MPPT charge controller then skip the first few steps.
Arduino MPPT Solar Charge Controller v3 – [Link]
Pico Technology has announced that its 3000D Series oscilloscopes launched in October last year now offer deeper memory. This comes on the back of last November’s release of beta drivers for Mac OS X and Linux operating systems for their range of oscilloscopes and data loggers adding to the existing Windows driver. This makes them suitable for use with the BeagleBone Black and Raspberry Pi development boards.
All scopes in this range feature deep memory, allowing high sampling rates to be maintained even at slower sweep speeds for capturing long waveforms in fine detail. Sampling at 1 Gsample/s it can capture a 500 msec waveform (half a billion samples) while hardware acceleration takes care of smooth display updating.
PicoScopes with Deeper Memory – [Link]
MILPITAS, CA February 5, 2015 Linear Technology announces the LTC7138, a 140V inputcapable high efficiency buck converter that delivers up to 400mA of continuous output current. It operates from an input voltage range of 4V to 140V, making it ideal for a wide range of telecom, industrial, avionic and automotive applications. The LTC7138 utilizes a programmable hysteretic mode design to optimize efficiency over a broad range of output currents. It utilizes an internal 1.8 Ohm power MOSFET for robust, high efficiency operation. A user programmable output current limit can set output current from 100mA to 400mA as required by the particular application. The LTC7138 can be programmed with fixed output voltages of 1.8V, 3.3V or 5V, or a resistor divider can be used to program outputs from 0.8V to V . The LTC7138’s thermally enhanced MSOP offers additional pin spacing required for high voltage inputs. The combination of its MSOP and only four tiny externals provides a highly compact solution footprint for a wide array of applications.
LTC7138 – High Efficiency, 140V 400mA Step-Down Regulator – [Link]
by Susan Nordyk @ edn.com:
Extending Infineon Technologies’ OptiMOS 5 portfolio of power MOSFETs are 80-V and 100-V variants optimized for high switching frequencies used in synchronous rectification applications for telecom and server power supplies, as well as industrial applications such as solar, low-voltage drives, and power adapters. OptiMOS 5 devices slash on-resistance by up to 45% for 80-V parts and up to 24% for 100-V parts compared to the previous generation.
Additionally, the OptiMOS 5 80-V variant offers a 38% reduction in output charge and the 100-V variant a 25% reduction. Less output charge means reduced switching losses and lower voltage overshoot in hard switching topologies and synchronous rectification. Moreover, a reduction in gate charge of 24% for 80-V devices and 29% for 100-V devices also reduces switching losses, especially at light load operation and in applications requiring high efficiency throughout the entire load range.
Next-generation MOSFETs cut on-resistance – [Link]