Combining a wide input-voltage range, high efficiency and low stand-by losses, the R-78S regulator extends the working lifetime of singlecell batteries by maintaining a stable output all the way down to the cut-off voltage at which the battery is fully discharged.
This means that devices such as microcontrollers, wireless modules or IoT systems can be supplied from a single 1.5V cell, providing a longer run-time than systems powered by a conventional 3V button battery.
The first R-78S series device provided a stable 3.3V output from an input voltage ranging from 3.15V to 0.65V. Now RECOM has added two new parts:
• the R-78S1.8-0.1 offers a 1.8V output suitable for supplying a Bluetooth® radio transceiver, and operates from an input range of 0.65V to 1.3V
• the R-78S3.6-0.1 offers a 3.6V output for a LoRaWAN™ radio transceiver, and operates from an input range of 0.65V to 3.3V
The efficiency of the R-78S series can reach 93% at full load, and over 90% even at light loads. No-load current is 160μA, falling to 7μA when the Control pin is used.
An integrated under-voltage lock-out circuit protects rechargeable cells from damage due to deep discharging. The R-78S is certified as compliant with the new EN62368-1 standard.
RECOM has also produced the R-REF02-78S Reference Design Board, which provides a ready-to-use 3.3V power-supply design for Internet of Things devices.
- Continuous short-circuit protection
- Over-temperature protection
- Operating-temperature range: -40°C to 100°C
- Three-year warranty
- IoT sensors and transmitters
- Remote monitoring and data-logging systems
- Planned-maintenance systems
These boards provide several test points for measuring voltages and currents, to allow engineers to evaluate the R-78S’ wide input-voltage range, high efficiency and low stand-by losses, all of which extend the working lifetime of an AA battery.
Orderable Part Numbers:
Evaluation Board: R-78S3.3-0.1-EVM-1
Reference Design Board: R-REF02-78S