The TUSS4440 is a highly integrated transformer drive analog front end for industrial ultrasonic applications. The transducer drive stage consists of low-side complementary drivers that can be configured to drive an ultrasonic transducer through a step-up transformer. The device delivers constant current to the primary side of the transformer.
The receive signal path includes a low-noise linear amplifier, a bandpass filter, followed by a logarithmic gain amplifier for input dependent amplification. The logarithmic amplifier allows for high sensitivity for weak echo signals and offers excellent input dynamic range over full range of reflected echoes.
The drivers can be controlled directly through the microcontroller for complete customization of the burst signal, or can be programmed through SPI with a customizable burst length. The TUSS4440 can support a single transducer to send and receive burst signals, or can set up two transducers to split the send and receive functions.
- Integrated driver for transformer driven transducers and receiver stage with analog output for ultrasound applications
- 86-dB input dynamic range analog front-end
- First stage low noise amplifier adjustable to 10, 12.5, 15 and 20 V/V
- Configurable bandpass filter from 40 KHz to 500 KHz
- Wide-band logarithmic amplifier
- Supported transducer frequencies (controlled by external clock)
- For low-power applications
- Standby mode: 1.7 mA (typical)
- Sleep mode: 220 µA (typical)
- Configurable drive stage:
- Complimentary low-side drivers with current limit for transformer based transducer excitation
- Configurable burst patterns using IO1 and IO2 pins
- Outputs:
- Voltage output of the demodulated echo envelope on VOUT
- Input signal zero crossing comparator output on OUT3 pin
- Programmable VOUT threshold crossing on OUT4 pin
- Serial Peripheral Interface (SPI) for configuration by microcontroller (MCU)