The MAX4444/MAX4445 differential line receivers offer unparalleled high-speed, low-distortion performance. Using a three op amp instrumentation amplifier architecture, these ICs have symmetrical differential inputs and a single-ended output. They operate from ±5V supplies and are capable of driving a 100Ω load to ±3.7V. The MAX4444 has an internally set closed-loop gain of +2V/V, while the MAX4445 is compensated for gains of +2V/V or greater, set by an external resistor. A low-power enable mode reduces current consumption to 3.5mA. Using current-feedback techniques, the MAX4444/MAX4445 achieve 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 video and RF signal-processing applications.
The MAX4444 and MAX4445 are ultra‑high‑speed differential line receivers that operate from ±5 V supplies and drive 100 Ω loads to ±3.7 V. They use a three‑op‑amp instrumentation‑amplifier architecture, offering a fixed +2 V/V gain for the MAX4444 and an externally selectable gain for the MAX4445. A low‑power enable mode reduces quiescent current to 3.5 mA.
The handbook includes absolute maximum ratings, detailed DC and AC electrical characteristics, typical operating curves (gain, bandwidth, distortion, noise), pin descriptions, and design recommendations such as grounding, bypassing, and handling capacitive loads. Application notes cover video, RF, and data‑acquisition systems, with guidance on coaxial line driving and gain setting for the MAX4445.
| Bandwidth (−3 dB) | 550 MHz |
|---|---|
| Slew Rate (MAX4444) | 5000 V/µs |
| Closed‑Loop Gain (MAX4444) | +2 V/V |
| Quiescent Current (Enable Mode) | 3.5 mA |
| Output Voltage Swing (into 100 Ω) | ±3.7 V |
| Input Noise Voltage Density | 25 nV/√Hz at 100 kHz |
The MAX4444 has an internally set closed‑loop gain of +2 V/V.
The gain of the MAX4445 is set by an external resistor (R_GAIN) connected between the RG pins.
When EN is low, the device draws only 3.5 mA of quiescent current.
Both devices achieve a −3 dB bandwidth of 550 MHz.