company blog about TI ADS1212U 22-Bit Precision Wide Dynamicrange Delta-Sigma Analog To Digital Converters

TI ADS1212U 22-Bit Precision Wide Dynamicrange Delta-Sigma Analog To Digital Converters

Shenzhen Mingjiada Electronics Co., Ltd. is a renowned supplier of electronic components, providing a long-term and stable supply of the ADS1212U high-precision, wide dynamic range Δ-Σ analogue-to-digital converter. With its 22-bit high resolution, wide dynamic range, and ultra-low power consumption, it is an ideal choice for high-precision measurement applications.

【ADS1212U Product Overview】

The ADS1212U is a high-precision 22-bit Σ-Δ analogue-to-digital converter housed in an 18-pin SOIC package, specifically engineered for applications requiring high-resolution, low-noise measurement.

Combining Burr-Brown's (now part of TI) advanced Delta-Sigma technology, the ADS1212U delivers a wide dynamic range and exceptional linearity.

As a single-channel ADC, the ADS1212U operates from a single +5V supply, delivering 24-bit resolution with guaranteed 22-bit no missing codes performance.

Its differential input architecture is particularly suited for direct connection to sensors or low-level voltage signals, providing an ideal solution for precise acquisition of weak signals.

【ADS1212U Core Specifications】

Resolution and Architecture: 22-bit no missing codes, Delta-Sigma architecture

Sampling Rate: Up to 6.25 kS/s

Input Configuration: Differential input, effectively suppressing common-mode interference

Supply Range: 4.75V to 5.25V single supply

Power Characteristics: Low quiescent current of 185μA, power consumption only 6mW

Interface Type: Flexible SPI-compatible serial interface

Operating Temperature: Industrial range from -40°C to +85°C

【ADS1212U Key Technical Features】

High Resolution and Conversion Rate

The ADS1212U delivers 22-bit no-missing-code performance, with effective resolution flexibly adjustable based on output data rate:

At a 10Hz output data rate, effective resolution reaches 20 bits

At 1000Hz output data rate, 16-bit effective resolution is maintained

The chip's maximum sampling rate is 6.25kSPS, allowing flexible configuration to balance speed and precision.

Programmable Gain and Time Multiplier

The ADS1212U's integrated Programmable Gain Amplifier (PGA) supports five gain settings: 1, 2, 4, 8, and 16. It also provides an acceleration factor (TMR) option with five configurable levels: 1, 2, 4, 8, and 16. Note that the product of the gain value and acceleration factor must be less than or equal to 16. This design allows users to flexibly adjust gain and conversion rate according to application requirements.

Low Power Consumption

The ADS1212U exhibits outstanding power management, with a minimum power consumption of just 1.4mW and a typical supply current of 185μA. This characteristic renders it highly suitable for battery-powered portable devices and applications requiring prolonged continuous operation, such as underwater weak magnetic signal detection systems.

【Internal Structure and Operating Principles of the ADS1212U】

Architectural Composition

The ADS1212U employs a Δ-Σ (Delta-Sigma) architecture, integrating a second-order Δ-Σ modulator with a programmable digital filter. This architecture achieves high-precision conversion through oversampling and noise-shaping techniques.

The ADS1212U chip incorporates the following primary functional modules:

Programmable Gain Amplifier (PGA): Front-end signal conditioning

Second-order Δ-Σ Modulator: Core conversion unit

Programmable Digital Filter: Noise suppression and signal extraction

Modulation Control Unit: Coordinates workflow

Register Set: Stores configuration parameters

Clock Circuit: Provides timing control

Internal 2.5V Voltage Reference: Supplies conversion reference

Register Configuration

The ADS1212U incorporates five functional registers:

Instruction Register (INSR) – 8-bit register controlling read/write operations

Command Register (CMR) – 32-bit register setting chip operating modes

Data Output Register (DOR) – 24-bit register storing conversion results

Zero Calibration Register (OCR) - 24-bit register for zero calibration

Full-Scale Calibration Register (FCR) - 24-bit register for full-scale calibration

By flexibly configuring these registers, users can optimise the ADS1212U's performance to suit diverse application scenarios.

【ADS1212U Application Domains and Scenarios】

The ADS1212U's high precision enables it to play a vital role across multiple demanding domains:

In industrial process control, the ADS1212U can directly interface with sensors for temperature, pressure, flow, and other parameters, enabling precise acquisition of microvolt-level signals.

Within precision instrumentation, its 22-bit resolution and low-noise characteristics enhance the accuracy and reliability of measurement equipment.

Within medical diagnostic equipment like blood analysers, the ADS1212U ensures accurate digitisation of faint biological signals.

Smart transmitters utilise its differential inputs and SPI interface to achieve precise field signal acquisition and bidirectional communication.

Furthermore, the ADS1212U finds extensive application in portable instruments, weighing systems, pressure sensors, and chromatography analysis scenarios.