The LTC7860 is a high efficiency switching surge stopper with overvoltage and overcurrent protection for high availability systems. During normal operation the LTC7860 turns on an external Pchannel MOSFET continuously to pass the input voltage through to the output with minimum conduction loss. During an input overvoltage condition, the LTC7860 controls the external MOSFET to operate as a high efficiency switching DC/DC regulator to protect critical downstream components by limiting the output voltage and current. The LTC7860 has an input voltage operating range of 3.5V to 60V, which can be extended with external circuitry up to 200V and higher. In MIL-STD-1275 applications the LTC7860 protects devices operating from a 28V vehicle power bus which can reach as high as 100V for up to 500ms. The LTC7860 is ideal for industrial, avionics and automotive power applications including ISO7637, as well as positive high voltage distributed power Hot Swap systems.
LTC7860 – High Efficiency Switching Surge Stopper – [Link]
Dave talks about Tektronix’s new unreleased AGO3000 Gravity Compensated Oscilloscope with a high precision TCXO timebase with 2G tip-over gravity compensation.
eevBLAB #8 – New Tektronix AGO3000 Oscilloscope – [Link]
by Charles Murray @ edn.com:
The free ESD Suppression Selection Tool, from Littelfuse captures the environment where a circuit-protection device resides, and then runs a software simulation of the device. “This tool doesn’t evaluate our part as a standalone device because the part never operates as a standalone device,” said Chad Marak, director of semiconductor business development for Littelfuse. “It always operates with something else—an ASIC or an IC. You have to consider the whole system.”
Select circuit-protection devices with free online tool – [Link]
The LT®3744 is a fixed frequency synchronous step-down DC/DC controller designed to drive a LED load at up to 20A continuous or 40A pulsed. The peak current mode controller will maintain ±3% LED current regulation over a wide output voltage range, from VEE to VIN. By allowing VEE to float to negative voltages, several LEDs in series can be driven from a single Li-Ion battery with a simple, single step-down output stage. PWM dimming is achieved with the PWM pins. The regulated LED current is set with analog voltages at the CTRL pins. Regulated voltage and overvoltage protection are set with a voltage divider from the output to the FB pin. The switching frequency is programmable from 100kHz to 1MHz through an external resistor on the RT pin.
Additional features include an accurate external reference voltage, a control input for thermally derating regulation current, an accurate EN/UVLO pin, an open-drain output fault flag, OVLO, frequency synchronization, and thermal shutdown.
LT3744 – High Current Synchronous Step-Down LED Driver – [Link]
Arduino Project: Data Logging DS3231 SD card module and Arduino Nano DIY data logger
Arduino Project: Data Logging with DS3231 RTC, SD card module and Arduino Nano DIY data logger – [Link]
So we’re always cooking up hot new hardware in the Grav Corp labs. Recently, we’ve been working on a project using a 128×64 OLED screen with the SSD1306 controller. Adafruit is a good source of these displays, with an excellent library written by Limor Fried. The Adafruit_SSD1306 library makes it simple to use these displays with a variety of Arduinos, using either software or hardware SPI. However, we wanted a speed boost, and the Due looked like it could deliver, with its DMA (Direct Memory Access) capability.
SSD1306 OLEDs – DMA Library for Arduino Due – [Link]
I was designing an electronic clock to see time easier at night. And while at it, I came up with a nice idea:
Having used a lot of perfboards(dot pcb) to prototype my projects, I thought of a way to make a 7 segment display out of smd leds. Making a segment out of 2 common grounded leds..
I stumbled upon it while trying to determine a nice size for my clock. I drew a mask on perfboard with a marker. Later I redrew it and cut it out:
An SMD 4 digit 7 segment DIY display – [Link]
Ray Wang from RaysHobby has written an article on his ESPToy 1.2, a ESP8266 development board based on the Lua firmware:
A little while back I released the very first version of ESPToy — a ESP8266 Development Board with a few useful on-board components like color LED, button, and temperature sensor. It has a built-in ATmega644 microcontroller, and pin headers for plugging in a ESP-01 through-hole WiFI module. Shortly after that, I discovered the Lua firmware (named nodemcu) for ESP8266. At first I didn’t pay much attention — Lua is a new language that I’ve never used before, and I wasn’t sure if it’s worth my time learning about it. At the same time I was getting tired of the AT firmware (the original firmware that comes with ESP), partly because it’s not very stable, and partly because it’s complicated to use and involves an extra microcontroller to communicate with it.
Introducing ESPToy 1.2 (with Lua Firmware) – [Link]
MAKE has posted Alasdair Allan’s three part series concerning the ESP8266 MCU. Alasdair highlights the capabilities and limitations of this chip, the installation and use of a supporting version of the Arduino IDE, and how to create a breadboard adapter for the ESP-01 breakout board (pictured above.) [via]
ESP8266: Arduino compatible $5 MCU with WiFi – [Link]
An application note from TI, TPS6122x low input voltage, 0.7V boost converter with 5.5μA quiescent current (PDF!):
The TPS6122x family devices provide a power-supply solution for products powered by either a single-cell, two-cell, or three-cell alkaline, NiCd or NiMH, or one-cell Li-Ion or Li-polymer battery. Possible output currents depend on the input-to-output voltage ratio. The boost converter is based on a hysteretic controller topology using synchronous rectification to obtain maximum efficiency at minimal quiescent currents. The output voltage of the adjustable version can be programmed by an external resistor divider, or is set internally to a fixed output voltage. The converter can be switched off by a featured enable pin. While being switched off, battery drain is minimized. The device is offered in a 6-pin SC-70 package (DCK) measuring 2 mm x 2 mm to enable small circuit layout size.
TPS6122x low input voltage, 0.7V boost converter with 5.5μA quiescent current – [Link]