CS40L25: Next‑Gen Haptic Driver for Ultra‑Fast, Low‑Power Feedback Across Mobile, Automotive, and Wearables

As consumer devices shed physical buttons in favor of touchscreens, the need for high‑quality haptic feedback has surged. Cirrus Logic’s CS40L25 series addresses this demand with a fully integrated driver that powers linear resonant actuators (LRAs) and voice coil motors (VCMs) while delivering fast, crisp sensations.

The CS40L25 combines a high‑performance haptic driver, a programmable DSP, and a Class‑H boost converter into a single, low‑power package. The DSP runs real‑time algorithms with sub‑5 ms latency and can store over 50 programmable waveforms in on‑chip RAM, enabling developers to craft a wide array of tactile effects.

Key power‑management features include an ultra‑low‑power sleep mode (<20 µA) and an always‑on trigger listening mode. The Class‑H boost converter achieves 85 % overall efficiency, supports programmable voltages up to 11 V, and operates at a 2 MHz switching frequency with pulse‑skipping for idle periods.

Cirrus Logic’s CS40L25 boosts haptic performance, enhancing user experience in mobile, automotive, PCs, wearables, and gaming/VR.

Cirrus Logic’s haptic solution is more than a driver; it’s a complete package that includes hardware, firmware, and developer tools. This end‑to‑end approach allows OEMs to quickly prototype and iterate tactile sensations without needing separate algorithmic modules.

Comprehensive Waveform Creation

The accompanying waveform editor supports classic button clicks, scrolling, pinch‑zoom, sensor notifications, haptic bumps, high‑fidelity alerts, camera clicks, and even a ringtone builder. The tools can target any LRA or VCM actuator, making the CS40L25 versatile across form factors.

Engineering for a Real‑Button Feel

Achieving a convincing “click” requires fast actuation, precise control, and low latency. The CS40L25’s boost converter rapidly ramps the actuator voltage to 11 V, delivering a sharp response. Closed‑loop DSP algorithms monitor the actuator’s position in real time, enabling quick deceleration within 25 ms to create the crisp sensation users expect from a physical button.

With an overall response time of 4 ms, the CS40L25 meets the 25 ms benchmark that distinguishes real button clicks from delayed haptic cues. The on‑chip memory allows 50 customizable waveforms to be stored and recalled instantly, eliminating the need for microcontroller intervention and further reducing latency.

Variants Tailored to Market Needs

• CS40L25‑CWZR / CS40L25B‑CWZR – 30‑ball WLCSP, optimized for mobile and portable devices; currently in volume production.
• CS40L25B‑CNZR – 32‑pin QFN, commercial‑grade, suitable for PCs, laptops, and general consumer electronics.
• CS40L25B‑DNZA – AEC‑Q100 qualified, 32‑pin QFN with wettable flanks, designed for automotive infotainment touchscreens. Both commercial and automotive variants are in sampling.

Looking ahead, Cirrus Logic plans to integrate force‑sensing capabilities directly into the driver, further reducing size, power consumption, and latency while expanding the tactile vocabulary available to designers.

>> This article was originally published on our sister site, Electronic Products.