• High resolution transmitting waveform
• Up to 3.0A push-pull source-driving current
• 230VP-P maximum output, uses two DN2625 FETs
• Angle vector beamforming I-Q switcher matrix
• 8-bit apodization DAC and 7.5° angular resolution
• Flexible frequency-resolution trade-off
• Programmable aperture windowing
• 250MHz maximum sampling rate
• 25MHz ultrasound maximum frequency
• PWM modulation push-pull current source
• Focusing phase adjustment & chirp waveform
• Fast SPI interface
• 2.5V CMOS logic interface
• +5.0V single power supply
• Low second order harmonic distortions

The MD2131 is a high-speed, arbitrary waveform, push-pull source driver. It is designed for medical ultrasound imaging and HIFU beamforming applications. It also can be used in NDT, Sonar and other ultrasound phase-array focusing beamforming applications. The MD2131 consists of CMOS digital logic input circuits, an 8-bit current DAC for waveform amplitude control, and four PWM current-sources. These current sources are constructed with the high-speed, in-phase and quadrature current-switch matrix and the built-in sine and cosine angle-to-vector look-up table. The angular resolution of the vector table is 7.5O per step, with a total range of 48 steps. There are four logic input signals to control the in-phase and quadrature PWM push-pull current-source’s output timing, frequency, cycle in the burst and waveform envelope. The MD2131’s output stage is designed to drive two DN2625 depletion N-type MOSFETs. The MOSFET drains are connected to a center-tap ultrasound frequency pulse transformer. The secondary winding of the transformer can connect to the ultrasound piezo or capacitive transducer via a cable with a good impendence match. The MD2131 has a high-speed, SPI-compatible interface to achieve per-scan-line fast updating of the data register for changing the beamforming phase angles and apodization amplitudes.