Ultra-High-Speed, Low-Distortion – Differential-to-Single-Ended Line Receivers with Enable

The project presented here is a differential line receiver that offers unparalleled high-speed, low-distortion performance and is ideally suited for digital, video, and RF signal-processing applications. These receivers offer a small-signal bandwidth of 550MHz and have a high slew rate of up to 2000-3800V/µs. The board’s 120mA output capability allows it to be directly coupled to data acquisition systems. The project has been designed using the MAX4445 chip, which has a three-op amp instrumentation amplifier architecture. These ICs have symmetrical differential inputs and a single-ended output. The project operates from ±5V supply and is capable of driving a 100Ω load to ±3.7V.  MAX4445 is compensated for gains of +2V/V or greater, set by an external resistor R3. A low-power enable mode reduces current consumption to 3.5mA. Using current-feedback techniques, the MAX4445 achieves a 550MHz bandwidth while maintaining up to a 5000V/µs slew rate. Excellent differential gain/phase and noise specifications make these amplifiers ideal for a wide variety of digital, video, and RF signal-processing applications. It is important to make a Gold-plated high-quality PCB and use high-grade components and connectors to operate at high frequency.

Key Features

• Operating Power Supply +/-5V DC (Dual 5V DC)
• Output Current Drive 90 to 120mA (Load 30 Ohms)
• Output Swing +/-3.3V
• 2000-3800V/µs Slew Rate
• External Gain Selection AVCL ≥ +2V/V
• 550MHz -3dB Bandwidth
• -60dB SFDR at 5MHz
• Low Differential Gain/Phase: 0.07%/0.05°
• Low Noise: 25nV/ at fIN = 100kHz
• Low-Power Disable Mode Reduces Quiescent Current to 3.5mA
• PCB Dimensions 36.20 X 28.89 mm

Applications

• Data Acquisition
• Differential to Single-Ended Conversion
• High-Speed Differential Line Receiver
• High-Speed Instrumentation Amplifier
• Medical Instrumentation
• Twisted-Pair to Coaxial Converter