Overview
The AD5940BCBZ-RL7, produced by Analog Devices Inc., is a high precision, low power analog front end (AFE) designed for portable applications that require advanced electrochemical and impedance measurement capabilities. This device is particularly suited for applications such as electrochemical measurements, bioimpedance analysis, and continuous glucose monitoring. The AD5940 features two high precision excitation loops and a common measurement channel, enabling a wide range of measurements on sensors.
Key Specifications
| Parameter | Specification |
|---|---|
| Analog-to-Digital Converter (ADC) | 16-bit, 800 kSPS and 1.6 MSPS options |
| Measurement Capabilities | Voltage, current, and impedance measurement |
| Excitation Loops | Two high precision loops: low power DAC and potentiostat, high speed 12-bit DAC |
| Input Channels | Multiple external current and voltage inputs, internal channels for diagnostic measurements |
| Transimpedance Amplifiers (TIAs) | Low power TIA and high speed TIA with programmable gain and load resistors |
| Switch Matrix | Ultra low leakage, programmable switch matrix |
| Reference Source | Precision 1.82 V and 2.5 V on-chip reference source |
| Interface | SPI serial input/output, wake-up timer, interrupt controller |
| Power Supply | 2.8 V to 3.6 V, 1.82 V input/output compliant |
| Power Modes | Power-on reset, hibernate mode with low power DAC and potentiostat amplifier |
| Package | 56-lead, 3.6 mm × 4.2 mm WLCSP |
| Operating Temperature Range | −40°C to +85°C |
Key Features
- High precision analog front end for electrochemical and impedance measurements.
- Dual excitation loops: one for low power signals up to 200 Hz and another for high frequency signals up to 200 kHz.
- 16-bit ADC with 800 kSPS and 1.6 MSPS options, input buffers, antialias filter, and programmable gain amplifier (PGA).
- Ultra low leakage switch matrix and input multiplexer for flexible sensor connections.
- Internal and external current and voltage channels, including two TIAs with programmable gain and load resistors.
- Precision on-chip reference source for low drift performance.
- SPI interface, wake-up timer, and interrupt controller for efficient control and data transfer.
- General-purpose inputs/outputs (GPIOs) controlled by the AFE sequencer for cycle accurate control of external sensor devices.
- Low power consumption with hibernate mode to maintain sensor bias.
Applications
- Electrochemical measurements, including amperometric, voltammetric, and cyclic voltammetry.
- Electrochemical gas sensor measurements.
- Bioimpedance applications, such as skin impedance and body impedance analysis.
- Continuous glucose monitoring.
- Battery impedance measurements.
- Smart water/liquid quality monitoring.
- Bioelectric and biopotential measurement systems, such as ECG measurements when used with other AFEs like AD8233.
Q & A
- What is the primary function of the AD5940BCBZ-RL7?
The AD5940BCBZ-RL7 is a high precision, low power analog front end (AFE) designed for electrochemical and impedance measurements in portable applications.
- What are the key measurement capabilities of the AD5940?
The AD5940 can measure voltage, current, and impedance, and it includes multiple external and internal channels for these measurements.
- What types of excitation loops does the AD5940 feature?
The AD5940 features two excitation loops: one for low power signals up to 200 Hz and another for high frequency signals up to 200 kHz.
- What is the resolution and sampling rate of the ADC in the AD5940?
The ADC is 16-bit with sampling rates of 800 kSPS and 1.6 MSPS.
- How does the AD5940 manage power consumption?
The AD5940 operates from a 2.8 V to 3.6 V supply and features power-saving modes including hibernate mode to maintain sensor bias while minimizing power consumption.
- What interface options are available for the AD5940?
The AD5940 includes an SPI serial input/output interface, a wake-up timer, and an interrupt controller.
- What is the operating temperature range of the AD5940?
The AD5940 is fully specified for an operating temperature range of −40°C to +85°C.
- What package options are available for the AD5940?
The AD5940 is packaged in a 56-lead, 3.6 mm × 4.2 mm WLCSP.
- Can the AD5940 be used in bioimpedance applications?
Yes, the AD5940 is suitable for bioimpedance applications, including skin and body impedance measurements.
- How does the AD5940 support multiple sensor connections?
The AD5940 features an ultra low leakage, programmable switch matrix that allows for the connection of multiple electronic measurement devices to the same wearable electrodes.
