Analog Devices Inc./Maxim Integrated

The LT5400 is a quad resistor network with excellent matching specifications over the entire temperature range. Matching is also specified when the LT5400 is configured in a difference amplifier. This enhanced matching specification guarantees CMRR performance to be up to 2× better than independently matched resistors.All four resistors can be accessed and biased independently, making the LT5400 a convenient and versatile choice for any application that can benefit from matched resistors.These resistor networks provide precise ratiometric stability required in highly accurate difference amplifiers, voltage references and bridge circuits.The LT5400 is available in a space-saving 8-pin MSOP package, and is specified over the temperature range of –55°C to 150°C.ApplicationsDifference AmplifierReference DividerPrecision Summing /Subtracting

The LT5401 is an ultra-precision matched resistor network optimized for use with fully differential or difference amplifiers, and with excellent matching specifications over the entire temperature range. The LT5401 contains two strings of matched resistors, each providing three tap points. The resulting matched ratios are well suited for precisely setting a differential amplifier’s gain or attenuation.When used to configure differential or difference gain, the LT5401’s excellent ratio matching ensures high CMRR, low gain errors and low gain drift to levels far too difficult to achieve with discrete passive components. This high level of precision reduces calibration requirements in many applications and offers 10 times higher performance than a ±0.01% discrete solution.The LT5401 is available in a compact 10-lead MSOP package with exposed paddle for improved thermal performance over a temperature range of –55°C to 150°C.ApplicationsFully Differential AmplifiersDifference AmplifiersReference DividersPrecision Summing/Subtracting

The LT5502 is a 70MHz to 400MHz monolithic integrated quadrature IF demodulator. It consists of an IF limiter, quadrature down mixers, integrated lowpass filters, and divide-by-two LO buffers. The demodulator provides all building blocks for demodulation of I and Q baseband signals with a single supply voltage of 1.8V to 5.25V. The IF limiter has 84dB small-signal gain, and a built-in receive signal strength indicator (RSSI) with over 90dB linear range. The input referred noise-spectral-density is 1.45nV/√Hz, which is equivalent to a 4dB noise figure when the input is terminated with a 50Ω source. The integrated lowpass output filters act as antialiasing and pulse-shaping filters for demodulated I/Q-baseband signals. The 3dB cutoff frequency of the filters is about 7.7MHz. The VCO frequency is required to be twice the desired operating frequency to provide quadrature local oscillator (LO) signals to the mixers. The standby mode provides fast transient response to the receive mode with reduced supply current when the I/Q outputs are AC-coupled to a baseband chip.ApplicationsIEEE802.11High Speed Wireless LANWireless Local Loop

The LT5504 is an 800MHz to 2700MHz monolithic integrated measuring receiver, capable of detecting a wide dynamic range RF signal from -75dBm to +5dBm. The logarithm of the RF signal is precisely converted into a linear DC voltage. The LT5504 consists of RF/IF limiters, an LO buffer amplifier, a limiting mixer, a 3rd-order 450MHz integrated low pass filter, RF/IF detectors and an output interface. The ultrawide dynamic range is achieved by simultaneously measuring the RF signal and a downconverted IF signal obtained using the on-chip mixer and an external local oscillator. The RF- and IF-detected signals are summed to generate an accurate linear DC voltage proportional to the input RF voltage (or power) in dB. The output is buffered with a low output impedance driver.ApplicationsRSSI MeasurementsReceive AGCTransmit Power ControlASK and Envelope DemodulationGSM/TDMA/CDMA/WCDMA

The LT5514 is a programmable gain amplifier (PGA) with bandwidth extending from low frequency (LF) to 850MHz. It consists of a digitally controlled variable attenuator, followed by a high linearity amplifier. The amplifier is configured with two identical transconductance amplifiers, hard wired in parallel with individual dedicated enable pins. When both amplifiers are enabled (Standard mode), the LT5514 offers an OIP3 of +47dBm (at 100MHz). Power dissipation can be reduced when a single amplifier is enabled (Low Power mode). Four parallel digital inputs control the gain over a 22.5dB range with 1.5dB step resolution. An on-chip power supply regulator/filter helps isolate the amplifier signal path from external noise sources.The LT5514’s open-loop architecture offers stable operation for any practical load conditions, including peaking-free AC response when driving capacitive loads, and excellent reverse isolation.The LT5514 may be operated broadband, where the output differential RC time constant sets the bandwidth, or it may be used as a narrowband driver with the appropriate output filter.ApplicationsHigh Linearity ADC DriverIF Sampling ReceiversVGA IF Power Amplifier50Ω DriverInstrumentation Applications