1FEATURES
23• 8-Channel Complete Analog Front-End:
– LNA, VCA, PGA, LPF, and ADC
• Ultra-Low, Full-Channel Noise:
– 0.85nV/√Hz (TGC)
– 1.1nV/√Hz (CW)
• Low Power:
– 122mW/Channel (40MSPS)
– 74mW/Channel (CW Mode)
• Low-Noise Pre-Amp (LNA):
– 0.75nV/√Hz
– 20dB Fixed Gain
– 250mVPP Linear Input Range
• Variable-Gain Amplifier:
– Gain Control Range: 46dB
• PGA Gain Settings: 20dB, 25dB, 27dB, 30dB
• Low-Pass Filter:
– Selectable BW: 10MHz, 15MHz
– 2nd-Order
• Gain Error: ±0.5dB
• Channel Matching: ±0.25dB
• Distortion, HD2: –65dBFS at 5MHz
• Clamping Control
• Fast Overload Recovery: Two Clock Cycles
• 12-Bit Analog-to-Digital Converter:
– 10MSPS to 50MSPS
– 69.5dB SNR at 10MHz
– Serial LVDS Interface
• Integrated CW Switch Matrix
• 15mm × 9mm, 135-BGA Package:
– Pb-Free (RoHS-Compliant) and Green

APPLICATIONS
• Medical Imaging, Ultrasound
– Portable Systems

DESCRIPTION
The AFE5805 is a complete analog front-end device
specifically designed for ultrasound systems that
require low power and small size.
The AFE5805 consists of eight channels, including a
low-noise amplifier (LNA), voltage-controlled
attenuator (VCA), programmable gain amplifier
(PGA), low-pass filter (LPF), and a 12-bit
analog-to-digital converter (ADC) with low voltage
differential signaling (LVDS) data outputs.
The LNA gain is set for 20dB gain, and has excellent
noise and signal handling capabilities, including fast
overload recovery. VCA gain can vary over a 46dB
range with a 0V to 1.2V control voltage common to all
channels of the AFE5805.
The PGA can be programmed for gains of 20dB,
25dB, 27dB, and 30dB. The internal low-pass filter
can also be programmed to 10MHz or 15MHz.
The LVDS outputs of the ADC reduce the number of
interface lines to an ASIC or FPGA, thereby enabling the high system integration densities desired for
portable systems. The ADC can either be operated
with internal or external references. The ADC also
features a signal-to-noise ratio (SNR) enhancement
mode that can be useful at high gains.
The AFE5805 is available in a 15mm × 9mm, 135-ball BGA package that is Pb-free
(RoHS-compliant) and green. It is specified for
operation from 0°C to +70°C.