ISL9122A - Buck-Boost DC/DC Converter with Ultra-Low Quiescent Current for Powering Low Power Sensors and MCUs in Portable Wireless Devices

With the aim to provide an ultra-low quiescent current (IQ) for powering sensors, microcontrollers (MCUs), wireless devices, and other system components, Renesas Electronics has come up with a flexible buck-boost switching regulator with bypass mode, named ISL9122A. The all-new buck-boost regulator has joined the recently released ISL9123 buck regulator. The ISL9122A buck regulator and its predecessor-ISL9123 buck regulator are ultra-low IQ switching regulators that can power the Renesas RL78 Family of 8/16-bit ultra-low energy MCUs, RA Family of 32-bit MCUs with Arm Cortex-M Core, and the RE Family of embedded controllers for wearables and energy harvesting applications.

The 1.8V to 5.5V excellent battery output makes ISL9122A capable enough to extend the battery life of smart IoT devices powered by coin-cell, lithium, and multiple series alkaline batteries. The ISL9122A’s flexibility, dynamic voltage scaling, and lowest regulated standby power consumption make it the best option to choose from.

The regulator’s power boost up to 5.375V maximizes RF capabilities of IoT devices across their battery range. Its PFM and PWM functionality maximizes efficiency over the whole output current range. In forced PWM mode, the regulator always switches at 2.5MHz frequency, which improves the EMI performance of the system.

The ISL9122A buck-boost switching regulator’s ability to make fast transitions from no load to full load makes it ideal for powering the newest generation of devices. It implements dynamic voltage scaling (DVS) in I2C programmable 25mV steps and optimizes system power consumption.

Features of ISL9122A

• Ultra-low IQ <1.3 µA and low shutdown mode current of 7 nA to extend battery life
• High efficiency at light load (84% @ 10 µA) and 97% peak efficiency to reduce power drain and heat buildup
• Automatic and selectable forced bypass power-saving mode reduces IQ
• Wide input voltage range from 1.8V to 5.5V, works with multiple battery topologies
• Large adjustable output voltage range from 1.8V to 5.375V in 25mV increments
• Max output current up to 500mA (Vout = 3.3V, Vin = 3.6V)
• Ultra-small footprint with 1.8 x 1.0mm WLCSP package or 3x2mm DFN package saves board space

The ISL9122A buck-boost DC/DC converter is available from Renesas’ worldwide distributors for USD 0.89 (8-lead DFN package) and USD 0.78 (8-bump WLCSP package) each in 1,000-unit quantities. Also, you can buy ISL9122AIRN-EVZ with 3.3V default output (DFN) and ISL9122AIIN-EVZ with 3.3V default output (WLCSP) evaluation boards for evaluating device features and performance. These boards wear a price tag of USD 70.

Note: More technical information can be found in the ISL9122A datasheet linked at the bottom of this page and on the ISL9122A product page.