**LTC3337ACBZ-R7: A High-Efficiency, Nanopower Buck-Boost DC/DC Converter with Integrated Coulomb Counter**

In the rapidly expanding world of battery-powered IoT devices, wearables, and remote sensors, the paramount challenge remains power management. Maximizing operational lifetime from a single battery charge demands not only exceptional energy conversion efficiency but also precise knowledge of remaining energy. The **LTC3337ACBZ-R7 from Analog Devices** addresses this dual challenge head-on, combining a high-efficiency buck-boost DC/DC converter with an integrated coulomb counter in a single, compact solution.

At its core, the LTC3337 is a **nanopower buck-boost converter** that can seamlessly regulate its output voltage from input voltages above, below, or equal to the output. This is critical for applications powered by single-cell or multi-cell batteries, where the voltage decays over discharge cycles. The device maintains a **remarkably low quiescent current of just 500nA** when regulating in buck mode and a mere 65nA in ship mode, making it ideal for applications that spend most of their life in a sleep state. Its high efficiency, up to 93%, ensures minimal energy is wasted during conversion, directly translating to longer battery life.

The truly differentiating feature of the LTC3337 is its **integrated precision coulomb counter**. This sophisticated circuitry measures the net charge flowing into and out of the battery with high accuracy (±5% typical). By monitoring the precise amount of energy consumed, the system microcontroller can accurately calculate the **State-of-Charge (SoC)** of the battery, moving beyond unreliable voltage-based fuel gauging methods. This provides end-users with a reliable and predictable battery runtime indicator.

Key performance specifications include an input voltage range from 1.8V to 5.5V, making it compatible with a wide array of battery chemistries including Li-ion, alkaline, and coin cells. The output voltage is user-programmable from 1.8V to 5.0V. Housed in a tiny 3mm x 3mm 10-lead LGA package, it offers a feature-rich solution with a minimal PCB footprint.

Typical applications are vast, spanning **wireless sensor networks**, **asset tracking tags**, **medical monitoring patches**, and any system where long battery life and accurate fuel gauging are non-negotiable requirements.

**ICGOODFIND:** The LTC3337ACBZ-R7 is a standout power management IC that masterfully solves two critical problems for energy-conscious designs: extending battery life through ultra-low-power, high-efficiency conversion and enabling accurate runtime prediction with its integrated coulomb counter. It is an essential component for designing the next generation of intelligent, long-lasting portable devices.

**Keywords:** Nanopower Buck-Boost, Integrated Coulomb Counter, State-of-Charge (SoC), High-Efficiency DC/DC, Low Quiescent Current.