Linear Technology has introduced a voltage supply regulator chip that includes an interface to take care of charging, balancing and monitoring external supercaps (or batteries) for system power backup. Its wide 0.1 V to 5.5 V capacitor/battery voltage and 1.8 V to 5.25V system backup voltage ranges make it suitable for a wide range of backup applications using supercapacitors or batteries. A proprietary low noise switching algorithm optimizes efficiency with capacitor/battery voltages that are above, below or equal to the system output voltage.
The LTC3110 can autonomously transition from charge to backup mode or switch modes based on an external command. Pin-selectable Burst Mode operation reduces standby current and improves light-load efficiency, which combined with a 1 μA shutdown current make the LTC3110 ideally suited for backup applications. Additional features include voltage supervisors for charge direction control, end of charge and a general purpose comparator with open-collector output for interfacing with a microcontroller.
Voltage regulator with backup management – [Link]
Most new voltage regulator chips are based on some variant of the digital switch-mode design which offers better efficiency compared with the more traditional linear regulator designs. Linear Technology has bucked the trend by introducing a new three-terminal linear regulator which offers some significant improvements on earlier designs.
The LT3088 has an input range from 1.2 V to 36 V with an extended safe operating area (SOA) compared to existing regulators, making it ideal for high input-to-output voltage and high output current applications where older regulators limit the output. The LT3088 uses a current source reference, allowing a single resistor to set the output voltage from 0 V to 34.5 V (with 1.2 V dropout). This regulator architecture, combined with low millivolt line and load regulation, enables multiple ICs to be paralleled easily for heat spreading and higher output current. The on-chip trimmed 50 µA current reference is ±1% accurate. The regulation, transient response and output noise (27 µVRMS) are independent of output voltage thanks to its voltage follower architecture.
LT3088 – 800mA Single Resistor Rugged Linear Regulator – [Link]
by Richard Quinnell @ edn.com:
Aiming to simplify design and increase power density in industrial systems, Intersil has developed the ISL8817 synchronous buck controller. The device accepts DC input voltages from 4.5V to 60 V and produces a selectable output voltage between 0.6V and 54V at up to 20A output current. Able to operate over a wide switching frequency (100 kHz to 2 MHz) with a low duty cycle (40 nsec minimum on time), the controller is able to step down from a 48V source to a 1V output in a single stage. This allows industrial applications using a 48V power distribution bus to provide the many voltages that modern CPUs and FPGAs require without the need for an intermediate low-voltage stage. This both increases power density in such systems as well as reducing conversion losses.
Buck controller allows 48V to 1V direct step-down – [Link]
Housed in a tiny 1.6×1.2-mm, 0.6-mm thin package suitable for wearable electronics and other space-constrained battery-operated applications, the SC563 low-dropout regulator from Semtech provides two regulated outputs at up to 300 mA each, while its fixed output voltages eliminate the need for external resistor divider networks. The device’s ultra-small footprint and low dropout voltage of 180 mV enable designers to implement power supplies where small size and high efficiency are paramount.
The SC563 accepts an input supply voltage of 2.3 V to 5.5 V. It has separate input, output, and enable pins for each LDO channel. Using the lowest possible input voltage for each output voltage reduces the power loss for each rail. Quiescent current of just 50 µA for each channel helps extend battery life. The regulator also offers short-circuit, undervoltage lockout, and thermal protection to prevent device failures.
LDO regulator squeezes into wearables – [Link]
This project will provide 3.3 V @ 800 mA DC Regulated Supply. The project is based on the LM1117 Low-Dropout Linear Regulator. The LM1117-3.3 is a low dropout voltage regulator with a dropout of 3.3V @ 800mA of load current.
3.3V Voltage Regulator – [Link]
The LTM8056 from Linear Technology is a 58 VIN, buck-boost μModule® (micromodule) regulator which requires just a few external passive components to complete the regulator design. Included in the package are the switching controller, power switches, inductor and support components. The basic external components needed are a single resistor to set the switching frequency, a resistor divider network to set the output voltage together with input and output capacitors. Other features such as input and output average current regulation may be implemented with just a few additional components. The LTM8056 operates with an input voltage ranging from 5 V to 58 V and can supply a regulated output voltage between 1.2 V and 48 V. The SYNC input and CLKOUT signal output provide clock synchronization options.
High Voltage Buck-Boost Regulator – [Link]
by Steven Keeping:
Such is the popularity of DC-to-DC voltage converters (“switching regulators”)––due to their high efficiency across wide input- and output-voltage ranges––that chip makers have focused a lot of research dollars on squeezing the essential components of the devices into modules. These modules typically include pulse-width-modulation (PWM) controllers and switching elements in a single, compact package, easing the design work for the engineer.
However, until recently, it has proven difficult to include the energy-storage device (the inductor) inside the package. This has dictated that the engineer must specify, source, and design-in the inductor as a peripheral component, adding complexity and consuming board space. Now, a new generation of high-frequency switching regulators has enabled the use of smaller inductors enabling the devices to be housed inside the component vendor’s package.
The Advantages (and Drawbacks) of DC-to-DC Voltage Converters with Integrated Inductors – [Link]
by Susan Nordyk @ edn.com:
A family of pin-compatible synchronous step-down switching regulators with integrated power switches, the MIC28511/12/13 from Micrel, supplies up to 4 A of output current (MIC28513) and accepts a wide input supply range of 4.6 V to 70 V (MIC28512). The devices have an operating junction temperature range of -40°C to +125°C and come in very small 24-pin, 3×4-mm FCQFN packages.
The MIC28511/12/13 regulators are offered in both Hyper Speed Control and HyperLight Load architectures, which allow for high VIN (low VOUT) operation and fast transient response, while reducing the required output capacitance and providing good light-load efficiency. They furnish an adjustable output voltage as low as 0.8 V with guaranteed accuracy to within ±1%.
High-voltage buck regulators stay cool in tiny packages – [Link]
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 LT®3042 is a high performance low dropout linear regulator featuring LTC’s ultralow noise and ultrahigh PSRR architecture for powering noise sensitive RF applications. Designed as a precision current reference followed by a high performance voltage buffer, the LT3042 can be easily paralleled to further reduce noise, increase output current and spread heat on the PCB.
The device supplies 200mA at a typical 350mV dropout voltage. Operating quiescent current is nominally 2mA and drops to <<1μA in shutdown. The LT3042’s wide output voltage range (0V to 15V) while maintaining unitygain operation provides virtually constant output noise, PSRR, bandwidth and load regulation, regardless of the programmed output voltage. Additionally, the regulator features programmable current limit, fast start-up capability and programmable power good to indicate output voltage regulation.
LT3042 – 20V, 200mA, Ultralow Noise, Ultrahigh PSRR RF Linear Regulator – [Link]