12-Bit Monitor and Control System with Multichannel ADC, DACs, Temperature Sensor, and Current Sense
The AD7294 contains all the functions required for general-purpose monitoring and control of current, voltage, and temperature integrated into a single-chip solution. The device includes low voltage (±200 mV) analog input sense amplifiers for current monitoring across shunt resistors, temperature sense inputs, and four uncommitted analog input channels multiplexed into a SAR analog-to-digital converter (ADC) with a 3 μs conversion time. A high accuracy internal reference is provided to drive both the digital-to-analog converter (DAC) and ADC. Four 12-bit DACs provide the outputs for voltage control. The AD7294 also includes limit registers for alarm functions. The device is designed on Analog Devices, Inc., high voltage DMOS process for high voltage compliance, 59.4 V on the current sense inputs, and up to a 15 V DAC output voltage.
The AD7294 is a highly integrated solution that offers all the functionality necessary for precise control of the power amplifier in cellular base station applications. In these types of applications, the DACs provide 12-bit resolution to control the bias currents of the power transistors. Thermal diode-based temperature sensors are incorporated to compensate for temperature effects. The ADC monitors the high-side current and temperature. All this functionality is provided in a 64-lead TQFP or a 56-lead LFCSP operating over a temperature range of −40°C to +105°C.
GSM, EDGE, UMTS, CDMA, TD-SCDMA, W-CDMA, WiMAX
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
The EVAL-AD7294EBZ is a fully featured evaluation Board for the AD7294. The evaluation board can be operated in complete standalone mode or connected to a PC via a standard USB interface. When operated with a PC, software is provided enabling the user to perform detailed analysis of the ADC's performance. This software includes the technical note describing the operation and set up of the evaluation board.
Recommended Driver Amplifiers
- For applications requiring low cost, low temperature drift, good DC and AC precision , we recommend the AD8692 .
- For low power applications , we recommend the ADA4692-2 .
- For high speed, low noise, low distortion , we recommend the AD8022, AD8317 or the AD8362 .
- For applications requiring highest precision , we recommend the AD8606 .
Recommended External References
- For high output current applications , we recommend the ADR431 .
- For wide supply applications , we recommend the AD780 .
- For cost sensitive applications , we recommend the AD1582 or the ADR391 .
- For applications requiring the lowest noise performance and output trim adjust , we recommend the ADR441 .
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.
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.