Figure 8-1 shows a system configuration found in a variety of ultrasound applications. The TX7516 has two supply rails A (PHV_A/MHV_A) and B (PHV_B/MHV_B) that enable switching between multiple TX levels for 3-Level mode, and also enable transmitting 5-Level mode. Each supply channel (A or B) can both provide up to 2 A output current, and the two channels can be operated in parallel for a 4 A output mode. Two TX7516 are used to provide 32 TX channels, and eight TMUX9616x are used to multiplex the 32 TX channels to the 128 PZT elements (4:1 mux configuration). Supply A will transmit at ±100 V, and supply B will transmit ±60 V.

A very important system level requirement for good image quality is to target ≥40 dB for both HD2PC and HD1PC (harmonic distortion pulse cancellation). The entire system, including both the TX7516 pulser and TMUX9616x mux, must output a TX signal at ≥40 dB. TX7516 is a pulser with excellent output signal performance, performing higher than the ≥40 dB target. Additionally, TMUX9616x is an excellent multiplexer, having minimal and in many cases negligible impact on the HD2PC/HD1PC performance, keeping the output signal performance high for good image quality while also allowing to increase the number of PZT elements in the system without increasing the number of pulser TX channels.

An example system use case using the TX7516EVM with the TMUX9616x EVM was performed first with the TMUX9616x removed and replaced with a pass through connection. Second, the same system level use case was performed by removing the pass through connection and adding the TMUX9616x back into the signal path. For a ±100 V pulser supply in this system use case, transmitting in 3-level mode with 5 cycles at 5 MHz with a 100 Ω || 100 pF test load, TX7516 alone performed with an HD2PC of 49 dB and an HD1PC of 67 dB. For the same use case, adding in TMUX9616x into the signal path, the system performed with an HD2PC of 54 dB and an HD1PC of 60 dB. Therefore, in this use case the TMUX9616x has negligible impact on the system level HD2PC/HD1PC performance; TX7516, by itself, and TX7516 with TMUX9616x in its signal path perform at an HD2PC/HD1PC performance level well above 40 dB.

For more details on the HD2PC and HD1PC performance of TX7516 and TMUX9616x across multiple supply levels, see the Application Curves. Additionally, some example use cases are plotted in the time domain and frequency domain for observation.