Low Energy solutions and the latest Bluetooth 5.0 in mobile applications and IoT

Electronics designers often encounter obstacles beginning from designing a power block cooperating with a properly selected battery, through a microcontroller system, to choosing a communication module with an antenna. IoT applications also cannot be properly designed when the designer seprataes the development of electronic system assumptions from programming and software. This rule applies also to embedded modules, in particular in relation to mobile applications and cloud environments. Where single uW/s is at a premium, each element of the algorithm and system behaviour must be comprehensively designed, maintaining hardware-connectivity-software symbiosis.


Low Energy power supply systems for mobile and IoT applications
Standard application with the power supply system includes the LDO stabilizer because it is able to provide the maximum available energy. LDO is characterized by simplicity and voltage stability, and in the case of new systems it also has better parameters and much more functionalities. An example of a modern LDO stabilizer solution is STLQ020from STMicroelectronics. In addition to the classic SOT323 housing, this system is available in miniature versions as DFN6 (2 × 2 mm) and Flip-Chip 4 (0.8 × 0.8 mm). Current consumption by STLQ020 is only 0.4 μA without load and only 5 nA in off mode.

Housings for STLQ02 – a high energy saving LDO regulator
Version no. 1
Version no. 2
Version no. 3
STMicroelectronics STMicroelectronics STMicroelectronics
2 x 2 mm
0.773 x 0.773 mm
2.0 x 2.1 mm

DC/DC converters and mobile applications

DC/DC converters are recommended for mobile applications that require the highest power efficiency. Most often they are buck converters. Using Buck solutions is associated with many difficulties. To minimize interference, these converters require a well-thought outer design, careful selection of components and their proper placement.

For these reasons, it is worth considering using the new STMicroelectronics ST1PS02.synchronous converter. It can work with PWM filling close to 100% and, like in the previous version (ST1PS01), its ultra-low power consumption means that it has very high efficiency not only for high loads, but also for those below 1 mA. ST1PS02 has also a new function – an additional built-in key, thanks to which it is possible to selectively switch the inverter output voltage between receivers.


A power supply system with exceptional input voltage flexibility

Even the best designed power supply system requires access to stored energy (usually a battery) or renewal of stored energy (e.g. chargers powered from USB or solar panels). L6924D from ST Microelectronic is a proven system with exceptional flexibility of input voltage in the range of 2.5 – 12 V that ensures cooperation with single lithium-ion and polymer cells.

Its integrated design includes all power elements such as power MOSFET, reverse polarity blocking diode. The system performs current control and has thermal protection. The L6924D allows the user to program many parameters such as pre-charge current, current for fast charge mode, pre-charge threshold, end of charge threshold and charge time counter.

L6924D has the ability to work in two modes:

  • linear, constant CV voltage or constant CC current
  • quasi-pulse providing the ability to dissipate power


Noteworthy is also the possibility of communication with the microcontroller through diagnostic connectors enabling monitoring of the presence of the cell, termination of the charging process and protection against thermal overload.

Bluetooth 5.0 – new functions in the new data transmission standard

Relatively recently, a new standard for data transfer has appeared on the market under the name Bluetooth 5.0. The technology is supported by Android from version 8.0. The new data transmission standard has been implemented to improve the transmission parameters for IoT solutions using Bluetooth Low Energy.

The biggest benefits of using the new Bluetooth version are faster speed and wider range as well as higher energy savings. It is worth mentioning that the increase in coverage is at the expense of data transfer speed. If we take into account the short distances between devices, Bluetooth version 5.0 allows data transfer at a speed of 2 Mb/s. This is twice the value compared to the previous version 4.2. When we increase the distance between devices, the transmission speed using Bluetooth 5 may decrease. It is also worth noting that a big change is the ability to transfer data over a distance of up to 240 meters.

A detailed description of other Bluetooth 5.0 features such as doubled transmission speed or important issues in designing and implementation for Android, as well as security-related issues can be found here.


Hardware – connectivity – software in one place

Masters Co. offers a comprehensive service from the selection of suitable, proven components, through technical support, to prototyping and contract production. Masters also provides ready-made solutions that can be implemented in a new project saving time and funds. Thanks to the extensive cooperation of the R&D Masters department with proven partners, we also provide comprehensive support in the design of software.

Feel free to contact us rd@masters.com.pl.


The article was created with support of Liki Mobile Solutions.