AD8338Low Power, 18 MHz Variable Gain Amplifier | Evaluation Boards | 2 | Active | The AD8338 is a variable gain amplifier (VGA) for applications that require a fully differential signal path, low power, low noise, and a well-defined gain over frequency. Although the inputs are differential, the device can also be driven with a single-ended source if required.The basic gain function is linear-in-dB and is controlled by the voltage applied to Pin GAIN. The nominal gain range spans from 0 dB to 80 dB for control voltages between 0.1 V to 1.1 V with a slope of 12.5 mV/dB. The nominal gain range can be shifted up or down via direct access to Pin INPD and Pin INMD, the current inputs of the VGA. For example, driving the INPD and INMD pins with 50 Ω resistors shifts the gain range up by 20 dB, that is, 20 dB to 100 dB, and lowers the input referred noise of the device to 1.5 nV/√Hz. Additionally, the gain slope can be inverted via logic Pin MODE.The AD8338 includes additional circuit blocks to enable input offset correction and automatic gain control (AGC). DC offset voltages are removed by the offset correction circuit, which behaves like a high-pass filter whose corner is set with an external capacitor. The AGC function varies the gain of the AD8338 to maintain a constant rms output voltage. An externally applied voltage to Pin VAGC with respect to the voltage at Pin VREF sets the output rms amplitude. A capacitor from Pin DETO to ground sets the response time of the AGC circuit.The AD8338 offers additional versatility by providing access to the internal summing nodes of the VGA core and the output amplifiers. With the addition of a few external passive components, users can customize the gain, bandwidth, input impedance, and noise profile of the device to fit their application.The AD8338 uses a single-supply voltage of 3.0 V to 5.0 V and is very power efficient, consuming as little as 3 mA quiescent current at mid gain. The AD8338 is available in a 3 mm × 3 mm, RoHS-compliant, 16-lead LFCSP and is specified over the industrial temperature range of −40°C to +85°C.APPLICATIONSFront end for inductive telemetry systemsUltrasonic signal receiversSignal compression for driving an ADCAGC amplifiers |
AD8339DC to 50 MHz, Quad I/Q Demodulator and Phase Shifter | RF Demodulators | 2 | Active | The AD8339 is a quad I/Q demodulator configured to be driven by a low noise preamplifier with differential outputs. It is optimized for the LNA in theAD8332/AD8334/AD8335family of VGAs. The part consists of four identical I/Q demodulators with a 4× local oscillator (LO) input that divides this signal and generates the necessary 0° and 90° phases of the internal LO that drive the mixers. The four I/Q demodulators can be used independently of each other (assuming that a common LO is acceptable) because each has a separate RF input.Continuous wave (CW) analog beamforming (ABF) and I/Q demodulation are combined in a single 40-lead ultracompact chip scale device, making the AD8339 particularly applicable in high density ultrasound scanners. In an ABF system, time domain coherency is achieved following the appropriate phase alignment and summation of multiple receiver channels. A reset pin synchronizes multiple ICs to start each LO divider in the same quadrant. Sixteen programmable 22.5° phase increments are available for each channel. For example, if Channel 1 is used as a reference and Channel 2 has an I/Q phase lead of 45°, then the user can phase align Channel 2 with Channel 1 by choosing the correct code.The mixer outputs are in current form for convenient summation. The independent I and Q mixer output currents are summed and converted to a voltage by a low noise, high dynamic range, current-to-voltage (I-V) transimpedance amplifier, such as theAD8021or theAD829. Following the current summation, the combined signal is applied to a high resolution analog-to-digital converter (ADC), such as theAD7665(16-bit, 570 kSPS).An SPI-compatible serial interface port is provided to easily program the phase of each channel; the interface allows daisy chaining by shifting the data through each chip from SDI to SDO. The SPI also allows for power-down of each individual channel and the complete chip. During power-down, the serial interface remains active so that the device can be programmed again.The dynamic range is typically 160 dB/Hz at the I and Q outputs. The AD8339 is available in a 6 mm × 6 mm, 40-lead LFCSP and is specified over the industrial temperature range of −40°C to +85°C.APPLICATIONSMedical imaging (CW ultrasound beamforming)Phased array systemsRadarAdaptive antennasCommunication receivers |
AD834500 MHz Four-Quadrant Multiplier | Integrated Circuits (ICs) | 8 | Active | The AD834 is a monolithic, laser-trimmed four-quadrant analog multiplier intended for use in high frequency applications, with a transconductance bandwidth (RL= 50 Ω) in excess of 500 MHz from either of the differential voltage inputs. In multiplier modes, the typical total full-scale error is 0.5%, dependent on the application mode and the external circuitry. Performance is relatively insensitive to temperature and supply variations due to the use of stable biasing based on a band gap reference generator and other design features.To preserve the full bandwidth potential of the high speed bipolar process used to fabricate the AD834, the outputs appear as a differential pair of currents at open collectors. To provide a single-ended ground referenced voltage output, some form of external current-to-voltage conversion is needed. This may take the form of a wideband transformer, balun, or active circuitry such as an op amp. In some applications (such as power measurement), the subsequent signal processing may not need to have high bandwidth.The transfer function is accurately trimmed such that when X = Y = ±1 V, the differential output is ±4 mA. This absolute calibration allows the outputs of two or more AD834 devices to be summed with precisely equal weighting, independent of the accuracy of the load circuit.The AD834J, available in 8-lead PDIP and plastic SOIC packages, is specified over the commercial temperature range of 0°C to 70°C. The AD834A is also available in 8-lead CERDIP and plastic SOIC packages operating over the industrial temperature range of−40°C to +85°C. The AD834SQ/883B, available in an 8-lead CERDIP, operates over the military temperature range of −55°C to +125°C. S-grade chips are also available.Two application notes featuring the AD834 (AN-212 and AN-216) can be found at www.analog.com. For additional applications circuits, consult the AD811 data sheet. |
| Evaluation Boards | 1 | Active | |
| RF and Wireless | 1 | Unknown | |
AD8342Active Receive Mixer LF to 3 GHz | RF Evaluation and Development Kits, Boards | 2 | Active | The AD8342 is a high performance, broadband active mixer. It is well suited for demanding receive-channel applications that require wide bandwidth on all ports and very low intermodulation distortion and noise figure.The AD8342 provides a typical conversion gain of 3.7 dB with an RF frequency of 238 MHz. The integrated LO driver presents a 50 Ω input impedance with a low LO drive level, helping to minimize the external component count.The differential high impedance broadband RF port allows for easy interfacing to both active devices and passive filters. The RF input accepts input signals as large as 1.6 Vp-p or 8 dBm (relative to 50 Ω) at P1dB.The open-collector differential outputs provide excellent balance and can be used with a differential filter or IF amplifier, such as theAD8370,AD8375,AD8351,AD8352, orADL5561. These outputs can also be converted to a single-ended signal using a matching network or a balun transformer. The outputs are capable of swinging 2Vp-p when biased to the VPOS supply rail.The AD8342 is fabricated on an Analog Devices, Inc., proprietary, high performance SiGe IC process. The AD8342 is available in a 16-lead LFCSP. It operates over a −40°C to +85°C temperature range. An evaluation board is also available.APPLICATIONSCellular base station receiversISM receiversRadio linksRF instrumentation |
| RF and Wireless | 2 | Active | |
| Evaluation Boards | 2 | Active | |
AD8345140 MHz to 1000 MHz Quadrature Modulator | Development Boards, Kits, Programmers | 3 | Active | The AD8345 is a silicon RFIC quadrature modulator, designed for use from 140 MHz to 1000 MHz. The part provides a very low noise floor and high output power supporting a significant improvement in output dynamic range. The AD8345 needs a low LO drive level and provides a fully specified 50 Ω buffered output.The part provides excellent amplitude and phase balance and sideband suppression specifications to enable higher order/capacity QAM modulated radios.Additionally the AD8345 has been tested and supports the requirements as an IF modulator within CDMA/GSM/W-CDMA cellular infrastructure equipment and as a direct conversion modulator for the 800 – 900 MHz cellular bands.The AD8345 is supplied in 16-lead Thin Shrunk Small Outline (TSSOP) package with exposed paddle, and fully specified over –40°C to +85°C temperature range.AVAILABILITYSamples part number (AD8345ARE) and an evaluation board, part number (AD8345-EVAL) are available.OTHER MODULATOR / DEMODULATOR PRODUCTSAD8346– 800 MHz to 2.5 GHz Lower Power Direct Up-Conversion ModulatorAD8347– 800 MHz to 2.7 GHz Direct Conversion DemodulatorAD8349– 700 MHz to 2.7 GHz Low Noise, Higher Output Drive, RF Modulator |
AD83462.5 GHz Direct Conversion Quadrature Modulator | RF and Wireless | 3 | Active | The AD8346 is a silicon I/Q quadrature modulator, designed to be used from 800 MHz to 2.5 GHz. The part is optimized for lower power applications, yet provides a very low noise floor and high output power for the given supply current.The AD8346 requires only −10 dBm LO drive level and provides a fully specified 50 ohm buffered output.The part provides excellent amplitude and phase balance and sideband suppression specifications to enable higher order/capacity QAM modulated radios.Additionally the AD8346 has been tested and provides −72 dBc ACPR when used in a direct up-conversion CDMA IS95 modulator.The AD8346 is supplied in 16-lead Thin Shrunk Small Outline (TSSOP) package, and fully specified over −40 to 85 degC temperature range.AVAILABILITYSamples part number (AD8346ARU) and an evaluation board, part number (AD8346-EVAL) are availableOTHER MODULATOR/DEMODULATOR PRODUCTSAD8345- 250 MHz - 1 GHz RF/IF Quadrature ModulatorAD8347- 800 MHz - 2.7 GHz RF/IF Quadrature DemodulatorAD8349- 800 MHz - 2.7 GHz Direct Up-Conversion Quadrature Modulator |
