Features and Benefits
- Dual independent digitally controlled VGA
- Differential input and output
- 150 Ω differential input
- Open-collector differential output
- 7.8 dB noise figure to 100 MHz @ maximum gain
- HD2/HD3 better than 77 dBc for 1 V p-p differential output
- −3 dB bandwidth of 130 MHz
- 41 dB gain range
- 1 dB step size ± 0.2 dB
- Serial 8-bit bidirectional SPI control interface
- Wide input dynamic range
- Pin-programmable output stage
- Power-down feature
- Single 5 V supply: 106 mA per channel
- 32-lead LFCSP, 5 mm × 5 mm package
The AD8372 is a dual, digitally controlled, variable gain amplifier (VGA) that provides precise gain control, high IP3, and low noise figure. The excellent distortion performance and moderate signal bandwidth make the AD8372 a suitable gain control device for a variety of multichannel receiver applications.
For wide input dynamic range applications, the AD8372 provides a broad 41 dB gain range. The gain is programmed through a bidirectional 4-pin serial interface. The serial interface consists of a clock, latch, data input, and data output lines for each channel.
The AD8372 provides the ability to set the transconductance of the output stage using a single external resistor. The RXT1 and RXT2 pins provide a band gap derived stable reference voltage of 1.56 V. Typically 2.0 kΩ shunt resistors to ground are used to set the maximum gain to a nominal value of 31 dB. The current setting resistors can be adjusted to manipulate the gain and distortion performance of each channel. This is a flexible feature in applications where it is desirable to trade off distortion performance for lower power consumption.
The AD8372 is powered on by applying the appropriate logic level to the ENB1, ENB2 pins. When powered down, the AD8372 consumes less than 2.6 mA and offers excellent input-to-output isolation. The gain setting is preserved when powered down.
Fabricated on an Analog Devices, Inc., high frequency BiCMOS process, the AD8372 provides precise gain adjustment capabilities with good distortion performance. The quiescent current of the AD8372 is typically 106 mA per channel. The AD8372 amplifier comes in a compact, thermally enhanced 5 mm × 5 mm 32-lead LFCSP package and operates over the temperature range of −40°C to +85°C.
- Differential ADC drivers
- CMTS upstream direct sampling receivers
- CATV modem signal scaling
- Generic RF/IF gain stages
- Single-ended-to-differential conversion
Product Lifecycle Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
AD8372-EVALZ is a fully populated, 4-layer, FR4-based evaluation board designed to allow easy evaluation of all features of the AD8372 DVGA. The evaluation board contains bypassable transformers to allow single ended or differential inputs and outputs on both DVGA channels, and a 25 pin D-Sub connector for external digital control of the on chip SPI port. This evaluation board requires only a single supply within the range of 4.5 V to 5.5 V.
Software & Systems Requirements
Tools & Simulations
Sys-Parameter models contain behavioral parameters, such as P1dB, IP3, gain, noise figure and return loss, which describe nonlinear and linear characteristics of a device.
ADIsimPLL enables the rapid and reliable evaluation of new high performance PLL products from ADI. It is the most comprehensive PLL Synthesizer design and simulation tool available today. Simulations performed include all key non-linear effects that are significant in affecting PLL performance. ADIsimPLL removes at least one iteration from the design process, thereby speeding the design- to-market.
ADIsimRF is an easy-to-use RF signal chain calculator. Cascaded gain, noise, distortion and power consumption can be calculated, plotted and exported for signal chains with up to 50 stages. ADIsimRF also includes an extensive data base of device models for ADI’s RF and mixed signal components.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.