Most PV solar regulators are buck (step down) regulators and require the PV panel voltage to be above the battery voltage. This design uses a buck-boost topology and allows the PV solar voltage to be above, below or equal to the battery voltage. For example, you could charge a 48V …
Cheap Lithium Battery “Active Balancer” boards have been turning up on Aliexpress and other eCommerce sites. But there has been some scepticism if they are genuinely active balancing and quite a few conflicting forum posts. Some have even claimed the ‘1R0’ inductors are actually 1 ohm resistors. The more traditional …
Motivation I have had the requirement to back-up small 5V low-powered devices such as a Foscam C1 security camera and a Raspberry PI based LoRaWAN concentrator. Many commonly available 5V Uninterruptible Power Supplies feature a two chip design with a Li-Ion battery charger to charge the back-up battery, and boost …
Designs based on the Texas Instrument’s bq24650 Synchronous Switch-Mode Battery Charge Controller for Solar Power With Maximum Power Point Tracking are commonplace on Aliexpress, ebay and Amazon. Consumers can purchase assembled PCBs, such as the one pictured above, or complete product enclosed in a relatively nice aluminium extruded housing. According …
The Atten ATZ97 / Maynuo M97 Series programmable DC loads has a RS-232 port that can be used for instrument control and acquisition. Rather than using more conventional text based SCPI (Standard Commands for Programmable Instruments) commands, these instruments use Modbus, a protocol designed for PLCs (Programmable Logic Controllers). The …
For far too long, I have been on the search for the ideal way to distribute power for low voltage systems, typically 12V. I have an small assortment of domestic networking gear, small embedded systems, LED desk lamps, battery chargers and USB chargers that operate from a backed-up 12V PV …
For the past couple of years, I have been powering my Sony 55” LCD TV and charging a couple of laptop computers from a 12V solar system. Both the Sony TV and the laptop computers have an input voltage of 19.5VDC. To step up the voltage from the battery, I …
The RakWireless RAK8213 is a Quectel BG96 based 4G LTE Cat M1/Cat NB1/EGPRS modem in a PCI Express MiniCard Form Factor. LTE categories M1/NB1 combined with innovations including Power Saving Mode (PSM) and Extended Discontinuous Reception (eDRX) can rival power consumption and battery life of other IoT Technologies such as LoRa and Sigfox. …
Linux 4.8 introduced a new GPIO user space subsystem for accessing GPIO. This tutorial provides an introduction to the new Character Device GPIO and explores how to control GPIO from the command line. sysfs GPIO User-mode GPIO (General Purpose Input/Output) has historically been performed via the legacy “integer-based”sysfs pseudo file system. For …
The FTDI FT2232H Hi-Speed Dual USB UART/FIFO Breakout Board provides a variety of standard serial and parallel interfaces: Asynchronous UART JTAG I2C SPI Parallel FIFO The board includes two linear regulators offering either 3.3V or 2.5V IO. An on-board Serial EEPROM stores custom USB descriptors, VID/PIDs and configurations. Design Files Design …
U-Boot U-Boot (The Universal Bootloader) is a popular, feature rich, open source bootloader for embedded systems. It is licenced under the GNU General Public Licence version 2. While its primary purpose is to boot an operating system, such as Linux, it also provides many useful tools for developing and debugging …
The RN2903 Wireless LoRa Module from Microchip ships with an on-board LoRaWAN Class A protocol stack. This stack can be accessed via ASCII based commands over a UART interface. For many, this is the interface of choice, offloading the complexity of the LoRaWAN stack to a dedicated processor contained within …
A breakout board for Microchip’s series of LoRa transceiver modules: RN2483 fully-certified 433/868 MHz Module (Europe) RN2903 fully-certified 915 MHz Module (North America, Australia) The RN2483/RN2903 LoRa modules contain a Microchip PIC18LF46K22 MCU with a Semtech SX1276 radio transceiver and is intended as a complete certified solution with LoRaWAN Class A protocol stack and …
This design is intended to recharge Maxell ML2032 Lithium Manganese Dioxide rechargeable coin cell batteries with a nominal voltage of 3.0V. These are ‘special’ coin cell batteries designed specifically as a rechargeable secondary cell. It is not recommended to attempt to recharge a primary CR2032. These cells have not be …
This board is a Raspberry PI Hat for the RAK833 LoRa Concentrator Gateway Module. It is smaller version of the popular RAK831. The RAK831 is larger, about the same footprint than a Raspberry PI and requires a breakout board to convert the RAK831’s 24 pin connector to the Raspberry PI’s …
The 12V 7Ahr “alarm” battery is still a safe, dependable choice for stationary back-up supplies, running items such as LED lighting or modem/routers. Using two Keystone 3571 female PCB terminals, this PCB assembly attaches directly to the terminals of a 12V 7AH SLA Battery (with 4.75mm spade terminals) and provides a low voltage …
Copyright 2019 • Craig Peacock • Adelaide • Australia