Renesas Announces Buck-Boost DC/DC Converter with Ultra-Low Quiescent Current for Powering Sensors, MCUs, Wireless Devices, and Other Components

Renesas Electronics introduced the ISL9122A, a flexible buck-boost switching regulator with bypass mode that provides ultra-low quiescent current (I_Q) for powering sensors, microcontrollers (MCUs), wireless devices, and other system components. Operating with battery output from 1.8 V to 5.5 V, the ISL9122A extends the battery life of smart IoT devices powered by coin-cell, lithium and multiple series alkaline batteries. Target applications include wireless earbuds, fitness bands, smart watches, water and gas meters, portable medical devices, and a wide range of battery-operated smart IoT devices.

The ISL9122A buck-boost switching regulator implements dynamic voltage scaling (DVS) in I²C programmable 25 mV steps to optimize system power consumption. The regulator’s power boost up to 5.375 V 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 2.5 MHz frequency, which improves EMI performance of the system.

Key Features of ISL9122A Buck-Boost Regulator with Bypass

• Ultra-low I_Q <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 I_Q
• Wide input voltage range from 1.8 V to 5.5 V, works with multiple battery topologies
• Large adjustable output voltage range from 1.8 V to 5.375 V in 25 mV increments
• Max output current up to 500 mA (V_OUT = 3.3 V, V_IN = 3.6 V)
• Ultra-small footprint with 1.8 × 1.0 mm WLCSP package or 3 × 2 mm DFN package saves board space
• Only requires three external components: one inductor, and input and output capacitors
• Full protection against overcurrent, short-circuit and overheating

Pricing and Availability

The ISL9122A is available now from Renesas’ worldwide distributors and is priced at $0.89 USD (8-lead DFN package) and $0.78 USD (8-bump WLCSP package) each in 1,000-unit quantities.

Two ISL9122A evaluation boards that allow designers to evaluate device features and performance are also available: The ISL9122AIRN-EVZ with 3.3 V default output (DFN) and ISL9122AIIN-EVZ with 3.3 V default output (WLCSP), both priced at $70 USD.

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ISL9122AIIN-EVZ Evaluation Board.