TI TX7332ZBX

The TX7332 is a highly integrated, high-performance transmitter solution for ultrasound imaging systems. The device features 32 pulser circuits (PULS) and 32 transmit/receive (T/R) switches, supporting both on-chip and off-chip beamformers (TxBF). It also integrates an on-chip floating power supply to reduce the number of required high-voltage power rails. The TX7332 incorporates a pulser circuit that generates three-level high-voltage pulses (up to ±100V) for exciting multiple channels of ultrasound transducers. The device supports 32 outputs in total. The maximum output current is configurable from 1.2A to 0.3A. When the pulser generates high-voltage pulses, the T/R switches in the off state protect the receiver circuitry by providing high isolation between the high-voltage transmitter and the low-voltage receiver. When the transducer receives echo signals, the T/R switches turn on and connect the transducer to the receiver. The on/off operation of the T/R switches can be controlled either by external pins or by the on-chip beamforming engine built into the device. The T/R switches provide an impedance of 24Ω in the on state. Ultrasound transmission relies on excitation delay profiles across different elements to define the transmission direction, driving multiple transducer elements. This operation is referred to as transmit beamforming. The TX7332 supports interleaved pulsing across different channels to enable transmit beamforming. The device supports both off-chip and on-chip beamforming operation. In off-chip beamformer mode, the output transitions of each pulser and the on/off operation of the T/R switches can be controlled by external control pins. To eliminate the effects of jitter on external control signals, the device supports a synchronization feature. When synchronization is enabled, the external control signals are latched using a low-jitter beamformer clock signal. In on-chip beamformer mode, the delay profiles for pulses across different channels are stored within the device. The transmit beamformer delay resolution supported by the device is one beamformer clock cycle, with a maximum delay of 2^13 beamformer clock cycles. An internal pattern generator produces output pulse patterns based on the pattern profiles stored in the profile RAM. Up to 16 beamforming profiles and 32 pattern profiles can be stored in the profile RAM. On-chip beamforming mode reduces the number of control signals that must be routed from the FPGA to the device. The TX7332 is available in a 260-pin 17mm × 11mm NFBGA package, with a rated operating temperature range of -0°C to 70°C.

• 32-channel three-level pulser and active transmit/receive (T/R) switch
• Ultra-low power on-chip beamforming modes:
  • Receive-only mode: 0.45mW/channel
  • Transmit/receive mode: 16.4mW/channel
  • CW mode: 160mW/channel
  • Global power-down mode: 0.1mW/channel
• Three-level pulser:
  • Maximum output voltage: ±100V
  • Minimum output voltage: ±1V
  • Maximum output current: 1.2A to 0.3A
  • Maximum clamp current: 0.5A to 0.12A
  • Second harmonic: –45dBc at 5MHz
  • CW mode jitter: 100fs measured at 100Hz to 20kHz
  • CW mode close-in phase noise: –154dBc/Hz at 1kHz offset from 5MHz signal
  • –3dB bandwidth, 2kΩ || 120pF load: 20MHz (for ±100V supply), 25MHz (for ±70V supply)
• Active T/R switch with:
  • On/off control signal
  • Bandwidth: 50MHz
  • HD2: –50dBc
  • On-resistance: 24Ω
  • Turn-on time: 0.5μs
  • Turn-off time: 1.75μs
  • Transient glitch: 50mV_PP
• Off-chip beamformer with:
  • Jitter cancellation via synchronization function
  • Maximum sync clock frequency: 200MHz
• On-chip beamformer with:
  • Delay resolution: one beamformer clock cycle
  • Maximum delay: 2^13 beamformer clock cycles
  • Maximum beamformer clock speed: 200MHz
  • On-chip RAM for storage
• High-speed (up to 100MHz) 1.8V and 2.5V CMOS serial programming interface
• Automatic thermal shutdown
• No specific power supply sequencing required
• Compact package: 260-ball NFBGA (17mm×11mm), 0.8mm pitch

• Ultrasonic imaging systems
• Piezoelectric actuators
• Probe-integrated ultrasonic imaging