This application details how a dual-channel LDO may be used to provide a dynamic voltage scaling output. This function is useful when powering microcontrollers that have a wide operating voltage range: it is advantageous to lower the operating voltage of the MCU in order to achieve lower power consumption (when possible).
The MSP430G2001, for example, has a supply voltage range that varies depending on the system frequency and programming modes. As an example, when the system frequency is 1MHz and flash memory programming is not required, the supply voltage range spans from 1.8V to 3.6V. However, if flash memory programming is required, the supply voltage range contracts to 2.2V to 3.6V.
Dynamic Voltage Scaling with a Dual LDO – [Link]
The Smartphone Quick-Jack Solution repurposes the standard 3.5mm stereo audio jack found on most smartphones into a self-powered data channel that makes communication with these smartphones as easy as plugging a headset jack into the audio port. The hardware/software platform is designed for iPhone® and Android® smartphones. This project will make it easy to connect external devices into a phone. It gives smartphones application developers an easy way to add context-aware application features, input user and environment data, or connecting peripherals. And also provides end-product designers instant access to smartphones’ convenience, appealing user interface, and cloud connectivity.
This project is compatible with both Open Mobile Terminal Platform (OMTP) and American Headset Jack (AHJ) standards; the hardware identifies the type of headset automatically and configures the hardware accordingly. First, a comparator circuit detects the type of headset port Quick-Jack has been inserted into. The result is interpreted by the LPC800, which then configures an analog switch accordingly. The analog switch connects the right pin of the jack plug to the right signal on the circuit board (GND/MIC). Read the rest of this entry »
Limpkin has build a development board for the ESP8266-03:
The ESP8266 modules come with a pre-loaded firmware that will accept some commands through their UART interface (connect to wifi, open udp socket, send data to this IP…). Moreover, since Espressif recently released their SDK you can now load your own custom programs using the existing bootloader. To launch this bootloader you just have to connect some IOs to GND in a specific order.
However, anyone wanting to develop a project involving dozens of Wifi nodes has to start from somewhere, eg make a prototype of their future platform. That is why I developed this development board, so the prototyping stage is as simple as possible.
As you can see in the picture below the dev board breaks out all the ESP8266-03 IOs, includes a 3.3V LDO, a USB to UART converter, some logic and a button to automatically start the bootloader.
A development board for the ESP8266-03 – [Link]
This compact Fremont subsystem reference design accurately measures low voltage, 0 to 100mV, single-ended analog signals with a high-accuracy, 16-bit analog front end (AFE) complete with an isolated data path. The design optimizes the functions of an ultra-precision low-noise buffer (MAX9632); a highly accurate ADC(MAX11100); an ultra-high-precision 4.096V voltage reference (MAX6126); a 600VRMS monolithic data isolator (MAX14850); and low-dropout (LDO) regulators providing regulated +6V, +5V, and -5V power rails (MAX1659 and MAX1735).This one-of-a-kind AFE solution works in many applications requiring low-voltage input, high impedance, and high-accuracy analog-to-digital conversion.
Maxim Fremont: 16-Bit, High-Accuracy, 0 to 100mV Input, Isolated Analog Front-End (AFE) – [Link]
Of the many low-dropout (LDO) regulators used to regulate voltage in electronic systems, some are specifically designed for low-noise operation. The MAX8887 low-noise LDO, for example, achieves a noise voltage of only 42µVRMS over the 10Hz to 100kHz range. Applications such as the ultra-low-noise oscillators required in instrumentation, however, require even lower noise. To fulfill that requirement, this project features the MAX6126 and a combination of low-noise components and filtering that achieves an output noise of only 6nV/√Hz at 1kHz
Ultra-Low-Noise LDO – [Link]
To add to its growing family of voltage regulator solutions Linear Technology Corporation have announced the LT3061, a high-voltage, low-noise, low-dropout voltage linear regulator with active output discharge. The device can deliver up to 100 mA of continuous output current with a 250 mV dropout voltage at full load. The LT3061 features an NMOS pull-down that discharges the output when SHDN or IN is driven low. This rapid output discharge is useful for applications requiring power conditioning on both start-up and shutdown (e.g. high-end imaging sensors).
A single external capacitor provides programmable low noise reference performance and output soft-start functionality. The LT3061 has a quiescent current of 45μA and provides fast transient response with a minimum 3.3μF output capacitor. In shutdown the quiescent current is less than 3μA and the reference soft-start capacitor is reset.
A High Voltage LDO regulator – [Link]
Just when you thought all new voltage regulator chips were using switched-mode technology along comes X-REL semiconductor with a linear design. The company specializes in manufacturing high-reliability, high-temperature devices; its XTRM prefixed components have an operational temperature range from −60 to +230ºC.
The recently announced XTR70010 Ultra Low Drop Out linear regulator has a dropout voltage of just 0.9 V per Amp of output current at 230ºC. It operates with an input voltage between 2.8 and 5.5 V and can supply more than 1.5 A with no requirement on the minimum dropout at lower current. The output voltage can be defined with a resolution of 100 mV between 0.5 to 3.6 V (a total of 32 levels) using internal settings or by using a conventional external voltage divider network.
Novel ULDO Linear Regulator – [Link]
vpapanik demonstrates the EM-1712 magnetic on-off switch on the breadboard:
Ultra-low standby current (less than 0.1 mA) magnetic on-off switch based on the AKM micropower hall bipolar latch EM-1712 and Microchip MCP1801 3.3V LDO. Of course, any regulator with EN (or SHDN) pin can be used. Ideal for touchless power switching, e.g. battery operated devices in watertight enclosures.
Micropower magnetic on-off switch – [Link]
The TPS7H1x01 is a low dropout (LDO) linear regulator that uses a PMOS pass element configuration. It operates under wide range of input voltage, from 1.5 V to 7V while offering excellent PSRR. The TPS7H1x01 features a precise and programmable fold back current limit implementation with a very wide adjustment range
- Current share/parallel operation to provide higher output current
- Wide VIN range: 1.5 V – 7 V
- Applications: Power management – LDO, RF components VCOs, receiver, ADCs amplifiers, high voltage, high PSRR, low noise and clean analog supply requirement applications
TPS7H1101 – 1.5 -7V Input, 3 Amp, Ultra Low Dropout Regulator – [Link]
By Ashok Bindra:
The use of low-dropout regulators, popularly known as LDOs, is common in many applications today because they provide a simple and inexpensive way to regulate an output voltage that is stepped-down from a higher input voltage. In addition, linear LDO voltage regulators contribute very-low noise as compared to switching regulators.
Nonetheless, to keep system power consumption low, such regulators must also feature ultra-low quiescent current (IQ) while providing excellent dynamic performance to ensure a stable, noise-free voltage rail, suitable for driving IC loads such as microprocessors, FPGAs, and other devices on the system board.
Selecting the Right Ultra-Low Quiescent-Current LDO Regulator – [Link]