Southchip Releases High-Performance Piezo Fan Driver
2026-11-06
Today, Southchip launched SC3606, a high-performance piezoelectric fan driver, providing critical driving support for the large-scale deployment of piezo fans in space-constrained and power-sensitive scenarios. SC3606 supports a wide input voltage range of 2.1V to 5.5V and delivers a maximum output of 46Vpp. It integrates full-range frequency sweeping and real-time frequency tracking algorithms, enabling it to autonomously lock onto the optimal resonant point within the 15kHz to 40kHz range. Together with Southchip's previously launched piezoelectric micropump liquid cooling driver SC3601, it provides customers with diversified, one-stop system-level solutions.
Edge AI Cooling Bottleneck: Active Cooling Emerges as the Breakthrough
As edge AI computing power continues to surge, the NPU performance of flagship SoCs has entered the hundreds of TOPS range. Running large models locally continuously often results in power consumption of over ten watts, pushing local heat flux density beyond 100W/cm2. Traditional VC (Vapor Chamber) and graphite film solutions can only spread heat rather than dissipate it, and their response time is virtually zero. With passive cooling approaching its engineering limits, active cooling has officially taken the stage.
Among all active cooling approaches, the piezoelectric fan is considered one of the optimal solutions for thin and light terminals. It features no motor, bearing, rotating shaft, or mechanical friction – just a thin film vibrating at ultrasonic frequencies. It can achieve a thickness of less than 1mm, noise levels around 30dB, power consumption in the milliwatt range, and sub-millisecond response times. However, a piezo actuator cannot find its own resonant point or adjust its own power consumption. It requires a driver chip capable of outputting high voltage, precisely locking onto the resonant point, and operating with high power efficiency to achieve commercial scale.
SC3606: Bringing Active Cooling into Millimeter-Scale Chassis
SC3606 is a driver chip developed specifically by Southchip for piezo fans. It features an ultra-small FCQFN 22L package (2.3mm x 2.75mm x 0.55mm) and supports a wide input voltage of 2.1V to 5.5V, allowing it to connect directly to the battery rail. Its maximum output swing reaches 46Vpp (±23V), covering an output frequency range of 2kHz to 40kHz, and supports both sine wave and square wave driving waveforms. The chip integrates an internal charge pump and an energy recovery architecture. Equipped with an I2C digital front-end, it can directly interface with mainstream flagship SoCs and PMICs. Furthermore, SC3606 features optimal operating point identification, frequency sweeping, and real-time frequency tracking capabilities, supports low-latency startup, and integrates comprehensive protection mechanisms such as OVP, OTP, UVLO, and SCP to ensure stable and reliable system operation.
SC3606 boasts six core technical advantages:
Full-range sweeping + real-time frequency tracking for automatic locking of the optimal operating point. Piezo fans are typical resonant loads, and the resonant point continuously drifts due to individual device differences, assembly stress, temperature changes, and long-term aging. Southchip holds multiple patents in the fields of adaptive frequency tracking and optimal operating frequency point tracking for piezo fans. SC3606 integrates full-range sweeping and piecewise approximation sweeping, combined with real-time frequency tracking algorithms, to autonomously search for the optimal operating point with the 15kHz-40kHz range. Device manufacturers no longer need to perform production line calibration for each batch of piezo fans, nor do they need to write complex compensation strategies for temperature changes.
Wide voltage input, directly compatible with battery voltage. With an ultra-wide operating range of 2.1V to 5.5V, SC3606 can connect directly to the battery rail without the need for an additional LDO or front-end DC-DC, adapting to the increasingly lower supply voltages of silicon-anode batteries.
High voltage swing, delivering high airflow in a small size. SC3606 integrates a bidirectional buck-boost circuit, using a single chip to boost the battery voltage up to a maximum output swing of 46Vpp (±23V). With a streamlined external BOM and compact package, it provides sufficient driving capability with minimal PCB footprint.
Supports sine and square wave outputs. Traditional square wave driving generates rich harmonics, which can excite spurious vibration modes of the piezo oscillator and produce audible whistling. SC3606 also supports pure sin wave driving with low harmonic content, allowing the actuator to vibrate only in the target mode, effectively reducing noise.
Energy recovery architecture, returning reactive current to the battery. A piezo oscillator is essentially a large capacitor that repeatedly charges and discharges every cycle. SC3606 adopts an energy recovery architecture to recycle the energy stored in the capacitive load back to the power rail, significantly optimizing system power consumption.
Low-latency startup. The integrated I2C digital front-end of the SC3606 supports a 1.2V IO level, allowing direct interfacing with mainstream flagship SoCs and PMICs. The system's thermal management strategy can wake up SC3606 at any time and enable rapid oscillation for intelligent scheduling.
Application Scenarios
As edge AI continues to penetrate smartphones, tablets, and wearables, cooling capability is becoming a key variable determining terminal performance. With its ultra-thin, silent, low-power and fast-response characteristics, the piezo fan provides a new engineering path for active cooling in thin and light terminals. The launch of SC3606 marks Southchip's completion of a key layout in active cooling driver field, providing core driving support for piezo air cooling to move from concept to commercial use.
