TI AFE5832LPZAV

The AFE5832LP is a highly integrated analog front-end (AFE) solution designed for portable ultrasound systems requiring high performance, low power consumption, and a small form factor. The device employs a multi-chip module (MCM) containing two dies (one VCA die and one ADC die). The 32 channels of the VCA die are connected to the 16 channels of the ADC die. Each ADC channel alternately converts odd and even VCA channels. Each channel in the VCA die can be configured in one of two modes: time gain compensation (TGC) mode and continuous wave (CW) mode. In TGC mode, each channel comprises an LNA, a programmable attenuator (ATTEN), a programmable gain amplifier (PGA), and a third-order LPF. LNA gain can be programmed to 21dB, 18dB, or 15dB. The ATTEN supports an attenuation range of 0dB to 36dB with digitally controlled attenuation. The PGA offers gain options from 21dB to 27dB in 3dB steps. The LPF cutoff frequency can be set between 10MHz and 25MHz to support applications with different frequency requirements. In CW mode, the LNA output feeds into a low-power passive mixer with 16 selectable phase delays. Different phase delays can be applied to each analog input signal to perform on-chip beamforming. A harmonic filter in the CW mixer suppresses third- and fifth-order harmonics, enhancing sensitivity for CW Doppler measurements. The 16 channels of the ADC die can be configured to operate at either 12-bit or 10-bit resolution. ADC resolution can be traded off against conversion rate, with maximum speeds of 80MSPS and 100MSPS at 12-bit and 10-bit resolution, respectively. Since each ADC alternately converts two VCA channels, the maximum sample rate per channel across the 32 channels of the AFE is 40MSPS and 50MSPS in 12-bit and 10-bit modes, respectively. By design, ADC power consumption scales with the sample rate. The ADC output interface uses LVDS for easy interfacing with low-cost FPGAs. As an ultra-low-power AFE solution, this device is well-suited for systems with stringent battery life requirements. The AFE is available in a 15mm × 15mm 289-pin NFBGA package and is pin-compatible with the AFE5832 family.

• 32-channel AFE for ultrasound applications: LNA, attenuator, LPF, ADC, and CW mixer
• Digital Time Gain Compensation (DTGC) total gain range: 0dB to 48dB
• Low Noise Amplifier (LNA) with programmable gain: low current noise: 1pA/rtHz, gain: 21dB, 18dB, and 15dB, linear input range: up to 700mVPP
• Programmable attenuator (ATTEN): attenuation range (0.125dB step): 0 to 36dB
• Digital TGC engine
• 16 ADCs operable at 12-bit 80MSPS or 10-bit 100MSPS: each ADC converts two sets of inputs at half rate, 12-bit mode: 72dBFS SNR, 10-bit mode: 61dBFS SNR
• TGC mode power consumption: minimum 18.5mW/channel in low-power mode, 4nV/rtHz, 10-bit, 20MSPS, LVDS (2× rate); 27.8mW/channel in low-noise mode, 3nV/rtHz, 12-bit, 40MSPS; 24.4mW/channel in low-power mode, 4nV/rtHz, 12-bit, 40MSPS
• Excellent inter-device gain matching: ±0.5dB (typical)
• Harmonic distortion level: –55dBc
• Fast and consistent overload recovery
• Continuous Wave (CW) path features: –148dBc/Hz low close-in phase noise at 1kHz offset from 5MHz carrier, no-signal power consumption: 10mW/channel, phase resolution: λ/16, 3rd and 5th harmonic suppression: 12dB
• LVDS interface, speed up to 1Gbps
• Compact package: 15mm×15mm NFBGA-289

• Medical ultrasound imaging
• Non-destructive testing equipment
• Sonar imaging equipment
• Probe-integrated electronics