Buck-Boost for IoT Devices Includes Internal Battery Monitor and Ultra-low IqFebruary 08, 2020 by Paul Shepard
Ricoh Electronic Devices Co., Ltd. has launched for the IoT Field the RP605 series, an ultra-low quiescent current buck-boost dc-dc converter containing a battery monitor. The new IC is a next-generation product of the RP604 series, a buck-boost dc-dc converter featuring ultra-low quiescent current of 0.3µA.
As the IoT market expands, there appear rising calls for IoT devices which perform not only long operation or downsizing but also supervising the battery voltage with low power consumption.
The new RP605 series was fabricated by adding a battery monitoring function to the mass produced PR604 series, a buck-boost dc-dc converter with ultra-low quiescent current.
It achieves the input voltage of 1.8V to 5.5V, the quiescent current of typically 0.4µA (dc-dc section: 0.3µA, battery monitor (BM) section: 0.1µA), and can prolong the battery operating time of IoT devices. Other key specifications are as follows: the maximum output current of 300mA (at buck operation); the output voltage range of 1.6V to 5.2V; the output accuracy of ±1.5%.
The RP605 series has a battery monitor pin which makes it possible to construct a low supply current and high-accuracy battery monitoring circuit with a small number of external components. This will help shrink the size of IoT devices and reduce the supply current (the BM output voltage can be selected from VIN/3 or VIN/4).
The small WLCSP-20-P3 is adopted for the new product's package to enable high-density mounting.
Also, the DFN(PLP)2730-12 package (Mass production is scheduled in April, 2020) is under development to support wide varieties of applications.
Product Features of the RP605
The RP605 series is a buck-boost dc-dc converter with ultra-low supply current and the small package, suitable for IoT devices.
1. Battery Monitoring Function
While conventional methods require external resistors to divide the input voltage, the RP605 does not need them.
2. Ultra-low Quiescent Current
Achieving the quiescent current of 0.4µA dc-dc section: 0.3µA, BM section: 0.1µA) at no load, the RP065 contributes to long operation of IoT devices.
3. Wide Input Voltage Range
The wide input voltage range of 1.8V to 5.5V enables the RP605 to correspond to various batteries such as coin batteries, next-generation rechargeable batteries, capacitors, and so on. Furthermore, it can operate by as low as 1.8V input, which leads to prolongation of the battery operating time.
4. Small Packages and Small Mounting Space
The RP605 adopts two small packages: WLCSP-20-P3 (2.315 x1.71 x 0.36 (max) mm) and DFN(PLP)2730-12 (3.00 x 2.70 x 0.60 (max) mm). It will help reduce mounting space and achieve high-density mounting.