Analog Devices Inc./Maxim Integrated

The MAX4200–MAX4205 are ultra-high-speed, open-loop buffers featuring high slew rate, high output current, low noise, and excellent capacitive-load-driving capability. The MAX4200/MAX4201/MAX4202 are single buffers, while the MAX4203/MAX4204/MAX4205 are dual buffers. The MAX4201/MAX4204 have integrated 50Ω termination resistors, making them ideal for driving 50Ω transmission lines. The MAX4202/MAX4205 include 75Ω back-termination resistors for driving 75Ω transmission lines. The MAX4200/MAX4203 have no internal termination resistors.The MAX4200–MAX4205 use a proprietary architecture to achieve up to 780MHz -3dB bandwidth, 280MHz 0.1dB gain flatness, 4200V/µs slew rate, and ±90mA output current drive capability. They operate from ±5V supplies and draw only 2.2mA of quiescent current. These features, along with low-noise performance, make these buffers suitable for driving high-speed analog-to-digital converter (ADC) inputs or for data-communications applications.ApplicationsDigital-Transmission Line DriversHigh-Speed ADC Input BuffersHigh-Speed DAC BuffersIF/Communications SystemsWireless Local Area Networks (WLANs)

The MAX4207 logarithmic amplifier computes the log ratio of an input current relative to a reference current (externally or internally generated) and provides a corresponding voltage output with a default -0.25V/decade scale factor. The device operates from dual ±2.7V to ±5.5V supplies and is capable of measuring five decades of input current across a 10nA to 1mA range.The MAX4207's uncommitted op amp can be used for a variety of functions, including filtering noise, adding offset, and adding additional gain. A 0.5V reference is also included to generate an optional precision current reference using an external resistor, which adjusts the log intercept of the MAX4207. The output-offset voltage and the adjustable scale factor are also set using external resistors.The MAX4207 is available in a space-saving 16-pin thin QFN package (4mm x 4mm x 0.8mm), and is specified for operation over the -40°C to +85°C extended temperature range.ApplicationsAnalog Signal ProcessingMedical InstrumentationPhotodiode Current MonitoringPortable Instrumentation

The MAX4208/MAX4209 ultra-low offset and drift instrumentation amplifiers feature exceptional precision specifications, low power consumption, rail-to-rail output, excellent gain-bandwidth product, and buffered REFIN/MODE input in a very small µMAX® package. These devices use a spread-spectrum, autozeroing technique that constantly measures and corrects the input offset, eliminating drift over time and temperature and the effect of 1/f noise. This technique achieves less than 20µV offset voltage, allows ground-sensing capability, provides ultra-low CMOS input bias current and increased common-mode rejection performance.The MAX4208/MAX4209 provide high-impedance inputs optimized for small-signal differential voltages (±100mV). All devices provide a gain-bandwidth product of 750kHz.The MAX4208 provides an adjustable gain with two external resistors or unity gain with FB connected to OUT. The MAX4209 is available with a fixed gain of 100V/V with ±0.03% (typ) accuracy. Both devices include a reference input (REF) to level-shift the output, allowing for bipolar signals in single-supply applications. In both devices, REFIN/MODE is an input to a precision unity-gain buffer, which sets the REF voltage to level-shift the output. The internal REF buffer allows the reference to be set by a simple resistive divider or an ADC reference without any loading error.The MAX4208/MAX4209 operate with a 2.85V to 5.5V single-supply voltage and consume only 750µA of quiescent current (when the internal buffer is off) and only 1.4µA in shutdown mode. These amplifiers also operate with ±2.5V dual supplies with REF connected to ground and REFIN/MODE to VSS. The MAX4208/MAX4209 are available in space-saving 8-pin µMAX packages and are specified over the automotive operating temperature range (-40°C to +125°C).ApplicationsBattery-Powered Medical EquipmentDifferential Voltage AmplificationIndustrial Process ControlNotebook ComputersPrecision Low-Side Current SenseStrain-Gauge Amplifiers