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]
International Rectifier’s IR3846 is a member of the Gen3 SupIRBuck family of highly integrated synchronous voltage regulators. IR3846 is a compact DC-DC regulator with a single input supply without the need of an external VCC with its internal LDO and has a high current output of up to 35 A. Being part of the Gen3 SupIRBuck family, it has a corrective and unique modulation feature that gives a jitter-free and noise-free operation allowing higher frequency and higher bandwidth operation for better transient response. The device is very efficient and ideal for power applications of enterprises requiring space such as netcom server/storage, distributed point-of-load power architecture, and embedded telecom systems that involve high power density.
With a market price of $29, IRDC3846 evaluation board is highly efficient and cost-effective having multiple features. The PCB is a 200 mm^2, 6-layer board mounted with few passive components. Some of the important features of the board include: digital soft-start up, power good operation, overvoltage protection, thermal shutdown, and programmable switching frequency, which is flexible for different applications ranging from 300 kHz-1.5 Mhz. It is designed to a well-regulated input supply of +12V and configured for remote differential sensing.
The IRDC3846 evaluation board is very easy-to-use. Simply connect a +12V input supply at VIN+ and VIN- and a maximum of 35 A load should be connected to VOUT+ and VOUT-. If external VCC is required in an operation, Vin and VCC pins should be shorted together by installing a 0 ohm resistor. Other than remote sensing, the board can also be configured for local sensing by changing the resistors needed for operation. The length of the on-board power ground is minimized for better efficiency. Using separate power ground and analog ground, both can be connected together using a 0 Ohm resistor.
If you need a low voltage, high current regulator, IR3846 definitely should be considered. Having a small footprint, the device has exceptional capability offering high density. It is likely suitable for many applications in network communication and storage systems.
International Rectifier SupIRBuckTM IRDC3846 Evaluation - [Link]
I grew fond of NXPs new LPC800 Cortex M0+ microcontrollers. I designed a small breakout for the LPC812 TSSOP20. This is the second revision. It includes push buttons for reset and activating the serial bootloader. The board has an integrated 500mA 3.3V LDO to supply both the MCU and connected devices from the USB port. The four pins on the top side (5V,RX,TX,GND) can be used to connect a cheap USB to serial adapter and program the device via the internal bootloader using FlashMagic.
LPC812 Breakout board - [Link]
Breakout board for micro SD cards:
This weeks PAW is just a breakout board for micro SD cards. There’s a number of boards like this on the market already, but they are kinda expensive and I like doing my own stuff, so here it is… The board have a LDO that supplies the SD card with 3.3 volts and there are proper level shifters on the board so it can connect to 5 volt devices. I’ve added a LED that will light up whenever a card is inserted and it will also double as a power indicator.
SD Card Breakout for breadboards - [Link]
This project details the design of a very low dropout adjustable power supply. A good power supply is essential to electronic projects, and being able to hook this up to a breadboard makes it very useful to hobbyists. It features a dropout of only 40mV – 400mV compared to 1.25V – 2.0V for a LM317 circuit. This means you can use a wider range of input/output voltages, including generating 3.3V from as low as 3.7V (such as 3 AA’s or a lithium ion battery)!
Low Dropout Adjustable Breadboard Power Supply - [Link]