Features and Benefits
- 14-bit resolution with no missing codes
- Throughput: 2.5 MSPS (TURBO high), 2.0 MSPS (TURBO low)
- Low power dissipation
15.5 mW at 2.5 MSPS, with external reference
28 mW at 2.5 MSPS, with internal reference
84 dB, with on-chip reference
84.5 dB, with external reference
- 4.096 V internal reference: typical drift of
- INL: ±0.25 LSB typical, ±1.0 LSB maximum
- Pseudo differential analog input voltage range
0 V to VREF with VREF up to 5.0 V Allows use of any input range
- No pipeline delay
- Logic interface: 1.8 V/2.5 V/2.7 V
- Serial interface: SPI-/QSPI-/MICROWIRE-/DSP-compatible
- Ability to daisy-chain multiple ADCs with busy indicator
- 20-lead, 4 mm × 4 mm LFCSP (QFN)
The AD7944 is a 14-bit, 2.5 MSPS successive approximation analog-to-digital converter (SAR ADC). It contains a low power, high speed, 14-bit sampling ADC, an internal conversion clock, an internal reference (and buffer), error correction circuits, and a versatile serial interface port. On the rising edge of CNV, the AD7944 samples an analog input, IN+, between 0 V and VREF with respect to a ground sense, IN−. The AD7944 features a very high sampling rate turbo mode (TURBO high) and a reduced power normal mode (TURBO low) for low power applications where the power is scaled with the throughput.
In normal mode (TURBO low), the SPI-compatible serial interface also features the ability, using the SDI input, to daisy-chain several ADCs on a single 3-wire bus and provide an optional busy indicator. The serial interface is compatible with 1.8 V, 2.5 V, and 2.7 V supplies using the separate VIO supply.
The AD7944 is available in a 20-lead LFCSP with operation specified from −40°C to +85°C.
- Battery-powered equipment
- Data acquisition systems
- Medical instruments
Markets and Technologies
Product Lifecycle Production
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.
Evaluation Kits (1)
The EVAL-AD7944FMCZ is a fully featured evaluation Kit for the AD7944. This board operates in conjunction with the System Development Platform board, EVAL-SDP-CH1Z. When operated with the System Development Platform board, software is provided enabling the user to perform detailed analysis of the ADC's performance. This software has an accompanying user guide describing the operation and set up of the evaluation board when operated with the System Development Platform board.
Tools & Simulations
Precision ADC Driver Tool
The Precision ADC Driver Tool is a web application that simulates the performance of precision ADC and driver combinations. Potential issues with driver selection, kickback settling, and distortion are flagged, and design tradeoffs can be quickly evaluated. Simulations and calculations include system noise, distortion, and settling of the ADC input
AD7944 Companion Parts
Recommended Driver Amplifiers
- For low noise, low power single-to-differential driver amplifier: ADA4941-1.
- For low noise and high frequency: ADA4897-1, ADA4898-1, ADA4899-1, AD8021.
- For a fully differential attenuating precision amplifier: AD8475.
- For low noise, small size and low power: ADA4841-1.
- For 5V single supply and low noise: AD8655.
Recommended External References
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.