## ADA4940-2ACPZ-R2: Ultra-Low Power ADC Driver The **ADA4940-2ACPZ-R2** is a high-performance, dual-channel, low-noise, fully differential amplifier designed primarily to drive high-resolution Analog-to-Digital Converters (ADCs). It is manufactured by Analog Devices and is widely used in precision data acquisition systems. --- ### 1. Key Technical Specifications | Parameter | Value | | :--- | :--- | | **Channels** | Dual (2 Amplifiers) | | **Gain Bandwidth Product** | 260 MHz | | **Slew Rate** | 95 V/µs | | **Voltage Noise** | 3.9 nV/√Hz | | **Supply Voltage Range** | 3.0V to 18V (Single) / ±1.5V to ±9V (Dual) | | **Current Consumption** | 1.25 mA per channel | | **Package Type** | LFCSP-24 (4mm x 4mm) | --- ### 2. Functional Description The ADA4940-2 acts as a bridge between single-ended signals and differential ADC inputs. Its primary roles include: * **Differential Conversion:** It efficiently converts single-ended or differential input signals to fully differential outputs, which is critical for reducing common-mode noise in ADCs. * **Adjustable Output Common-Mode:** It features a `VOCM` pin that allows the user to set the output common-mode voltage to match the optimal input range of the downstream ADC. * **Low Power Consumption:** With only 1.25 mA per amplifier, it is optimized for power-sensitive applications like portable medical devices or industrial sensors. --- ### 3. Application Examples * **ADC Driving:** Specifically designed for 16-bit and 18-bit Successive Approximation Register (SAR) ADCs (e.g., AD7982). * **Data Acquisition:** Used in multi-channel systems where high density and low power are required. * **Medical Imaging:** Employed in ultrasound and MRI front-ends for signal conditioning. * **Industrial Process Control:** Precise signal scaling and filtering in harsh environments. --- ### 4. Comparison: ADA4940-1 vs ADA4940-2 | Feature | ADA4940-1 | ADA4940-2 | | :--- | :--- | :--- | | **Channel Count** | Single | Dual | | **Package** | LFCSP-16 | LFCSP-24 | | **Best For** | Space-constrained single signals | Synchronous multi-channel sampling | --- ### 5. Part Number Breakdown ```text ADA4940 - 2 - ACPZ - R2 | | | | | | | └── Packing Code (7" Reel, 250 units) | | └───────── Package (Lead-frame Chip Scale Package, RoHS compliant) | └────────────── Number of Channels (Dual) └───────────────────── Product Family (Differential Amplifier) ```