Switching Regular’s Low Quiescent Current Extends Battery Life

Texas Instruments has introduced an ultra-low-power switching regulator with what TI claims is the industry’s lowest operating quiescent current (IQ) at 60 nA, a third that of the nearest competitive device. The TPS62840 synchronous step-down converter delivers very high light-load efficiency of 80% at 1-µA load, which can enable designers to extend the battery life of their systems, or use fewer or smaller batteries to shrink their overall power supply solution size and reduce cost. Additionally, the new DC/DC converter’s wide input voltage (VIN) range of 1.8 V to 6.5 V supports a variety of battery chemistries and configurations.

TI’s 60-nA IQ buck converter increases efficiency and shrinks solution size in a variety of battery-powered industrial and personal electronics applications

These features plus its selectable functions enable the TPS62840 to help engineers solve critical design challenges in many battery-powered, always-on industrial and personal electronics application –including narrow-band Internet of Things (IoT), grid infrastructure equipment and wearables–that require more flexibility, an extended wireless range, improved accuracy and reduced electromagnetic interference (EMI).

A lower IQ draw delivers longer battery life for systems with very light loads (less than 100µA), and those operating primarily in standby/ship mode (not switching). The low IQ of the TPS62840 enables its 80% efficiency at a 1-µA load, which is up to 30% better than competitive devices.

The TPS62840’s selectable mode and stop functions improve noise performance and reduce signal distortion. These benefits can help lower the solution cost because designers can achieve system requirements without using more expensive precision signal-chain components, sensors or radio solutions to perform the same functions. The mode pin allows for continuous conduction mode, also called forced pulse-width modulation mode, to improve ripple or noise performance and lessen the impact on transmissions in sensitive radio-frequency applications. The stop pin turns off all switching to reduce EMI or ripple, and minimizes distortions passed to precision signal-chain, measurement, sensors or wireless connectivity components.

Engineers can use the new switching regulator to cut their battery count in half or use smaller batteries in their design. For example, designers can save up to 16,980 mm3 using four AAAs instead of four AAs.

Flexible VIN broadens applications: The TPS62840’s wide range of 1.8 VIN-6.5 VIN accommodates multiple battery chemistries and configurations, such as two lithium manganese dioxide (2s-LiMnO2) cells in series, single-cell lithium thionyl chloride (1xLiSOCL2), four-cell and two-cell alkaline, and lithium polymer (Li-Po).

Pre-production samples of the TPS62840 are now available through the TI store in the following packages: 8-pin small outline no-lead (SON), measuring 1.5 mm by 2.0 mm; 6-pin wafer chip scale package (WCSP), measuring 0.97 mm by 1.47 mm. An 8-pin thermally enhanced package (HVSSOP), measuring 3 mm by 5 mm, will become available later this year. Pricing starts at $0.85 in 1,000-unit quantities. The TPS62840-1DLCEVM55 and TPS62840-1YBGEVM56 evaluation modules are available for $49 each.

Texas Instruments | www.ti.com

 

Buck Converter Extends Battery Life of USB Type-C Gear

Maxim Integrated Products has announced the MAX77756, a 24 V, 500 mA, low quiescent current (IQ) buck converter. The product targets developers of multi-cell, USB Type-C products in need high current, dual inputs and I2C support. USB Type-C products must generate an always-on 3.3 V rail to detect USB insertions. Products utilizing the Power Delivery (PD) voltage range (5 V to 20 V) can generate an always-on (1.8 V /3.3 V /5.0 V) digital supply MAX77756_EVKit_imagerail for the port controller using the MAX77756 step-down converter. In addition, the MAX77756 has a 2 0 μA quiescent current that extends battery life by reducing idle power consumption. To simplify the system design, the MAX77756 has a dual input ideal diode ORing circuit that allows the chip to power from the external USB source if the battery is empty.

Multi-cell battery-operated devices—such as ultrabooks, laptops, tablets, drones and home automation appliances—can easily evolve to Type-C with PD using the flexible MAX77756 power supply. The MAX77756 has a unique combination of wide input voltage range, low quiescent current, higher current load, dual input, and I2C for flexibility and programmability. There is also a default power mode if customers do not want to use the I2C bus. The MAX77756 is a robust IC with short-circuit and thermal protection, 8ms internal soft-start to minimize inrush current, proven current-mode control architecture, and up to 26V input voltage standoff.

Key Advantages

  • Low quiescent current: 1.5 μA Buck and 20 μA MUX for always-on operation
  • High efficiency: Up to 92% with integrated power MUX
  • Small solution size: 2.33mm x 1.42mm 15-bump WLP; no external Schottky array needed
  • Wide input voltage: Operates on full VBUS range (5 V – 20 V) and VBATT (2S, 3S, 4S Li+)

MAX77756 is available from stock and priced at $0.65 (10,000+)..An evaluation board MAX77756EVKIT# (see photo) is available from stock and priced at $70

Maxim Integrated Products | www.maximintegrated.com

Fully Integrated DDR Memory Power Solution

Texas Instruments recently launched a fully integrated power management solution for double date rate DDR2, DDR3, and DDR3L memory subsystems. Intended for use in automotive (e.g., infotainment and driver assistance systems) and industrial (e.g., measurement and automation) applications, the TPS54116-Q1 DC/DC buck converter is a 2.95-to 6-V input, 4-A synchronous step-down converter with a 1-A peak sink/source DDR termination and buffered reference. TPS54116-Q1 Press Photo

Used with WEBENCH online design tools, the TPS54116-Q1 buck converter simplifies power conversion and speeds up the power-supply design process. It provides up to 2.5-MHz switching frequency and minimizes solution size by integrating the MOSFETs and reducing inductor size. The switching frequency can be set above the medium-wave radio band for noise-sensitive applications. Furthermore, it is synchronizable to an external clock.

The converter is packaged in a thermally enhanced 24-pin, 4 mm × 4 mm × 0.75 mm very thin quad flat no-lead (WQFN) package. It costs $2.50 in 1,000-unit quantities.

Source: Texas Instruments

SWIFT DC/DC Buck Converters Reduce EMI

Texas Instruments recently launched the industry’s first 20-A and 30-A synchronous DC/DC buck converters with frequency synchronization for low-noise and reduced EMI/EMC and a PMBus interface for adaptive voltage scaling (AVS). The SWIFT 20-A TPS544B25 and 30-A TPS544C25 converters integrate MOSFETs and feature small PowerStack QFN packages to drive ASICs in space-constrained and power-dense applications. When used with TI’s WEBENCH online design tools, the converters simplify power conversion and speed the power supply design process. TI Swift

The highly integrated converters feature 0.5% reference-voltage accuracy, as well as full differential remote-voltage sensing. Frequency synchronization to an external clock eliminates beat noise and reduces EMI. Moreover, the TPS544B25 and TPS544C25 offer pin-strapping that enables the devices to start up without PMBus commands to an output voltage set by a single resistor. Programmability, real-time monitoring of the output voltage, current and external temperature, and fault reporting via PMBus simplify power-supply design, increase reliability, and reduce component count and system cost.

Together, the TPS544C25 and UCD90240 provide a complete PMBus point-of-load (POL) and sequencing solution. Download the Complete PMBus Power System for Enterprise Ethernet Switches TI Designs reference design.

TPS544B25 and TPS544C25 key features and benefits:

  • Integrated power MOSFETs support 20-A and 30-A of continuous output current.
  • On-chip PMBus interface and non-volatile memory simplify power-supply design and enable customization. Read a blog post on “PMBus – what is the value anyway?”
  • Voltage-control mode with input feed-forward improves noise margin and responds instantly to input voltage changes.
  • Other features include internal soft start, input under-voltage protection, thermal shutdown and a reset function.

The TPS544B25 costs $4.08 in 1,000-unit quantities. The TPS544C25 is $4.49 in 1,000-unit quantities. Evaluation modules are available.

Source: Texas Instruments

Highly Integrated DC/DC Converter with PMBus Digital Interface

Texas Instruments recently introduced a four-channel buck DC/DC converter with PMBus/I2C digital interface for applications in space-constrained equipment. The TPS65400 dual- or quad-output configurable DC/DC converter integrates eight power MOSFETs. In addition, it features industry-leading efficiency at up to 95% in the smallest footprint.TPS65400 Press Photo

The TPS65400 includes four high-current synchronous buck switching regulators with integrated MOSFETs. Each switching converter supplies a 2- or 4-A output to efficiently power digital circuits, such as the processor, FPGA, ASIC, memory and digital input/output. Switching frequency for the converter is independently adjustable up to 2.2 MHz. The TPS65400 can be powered from a single-input voltage rail between 4.5 and 18 V. It supports applications running off a 5- or 12-V intermediate power distribution bus.

The TPS65400’s benefits and key features include:

  • Flexible power up/down sequencing control increases system reliability.
  • Parameter configuration and status monitoring via PMBus
  • Dynamic voltage scaling to optimize processor performance
  • Phase interleaving reduces input capacitance and ripple
  • Current sharing supports higher output current and enhances design flexibility
  • Small 48-pin VQFN package measures 7 mm × 7 mm × 0.9 mm.

The TPS65400 costs $3.68 in 1,000-unit quantities. The TPS65400EVM-678 evaluation module costs $199.

Source: Texas Instruments