STHV748SQ Quad ±90 V, ±2 A, 3/5 level, ESD-enhanced high-speed ultrasound pulser

This monolithic, high-voltage, high-speed pulser generator features four independent channels. It is designed for medical ultrasound imaging applications, but can also be used to drive piezoelectric, capacitive or MEMS based transducers.

The STHV748S is composed of a controller logic interface circuit, level translators, MOSFET gate drivers, noise blocking diodes, and high-power P-channel and N-channel MOSFETs as the output stage for each channel. It also includes clamping-to-ground circuitry, anti-leakage, anti-memory effect block, thermal sensor, and a T/R switch which guarantees effective decoupling during the transmission phase. The STHV748S also includes self-biasing and thermal shutdown blocks.

Each channel can support up to five active output levels with two half bridges. The output stage of each channel is able to provide ±2 A peak output current. In order to reduce power dissipation during continuous wave mode, a dedicated half-bridge is available and the peak current is limited to 0.6 A.

An ESD reinforced structure was developed to prevent high voltage overshoots and inrush current due to cabled transducer reflections. Each HV output is supported by a dedicate HV diode network to withstand possible reflections, mitigating excessive voltage overshoot that could lead to device damage.