ADS7958SRGER vs ADC121S021CISDX/NOPB
| Part Number |
|
|
| Category | Data Acquisition - Analog to Digital Converters (ADC) | Data Acquisition - Analog to Digital Converters (ADC) |
| Manufacturer | Texas Instruments | Texas Instruments |
| Description | IC ADC 8BIT SAR 24VQFN | IC ADC 12BIT SAR 6WSON |
| Package | Bulk | Tape & Reel (TR) |
| Series | microPOWER™ | - |
| Features | - | - |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Package / Case | 24-VFQFN Exposed Pad | 6-WDFN Exposed Pad |
| Supplier Device Package | 24-VQFN (4x4) | 6-WSON (2.2x2.5) |
| Reference Type | External | Supply |
| Sampling Rate (Per Second) | 1M | 200k |
| Data Interface | SPI | SPI, DSP |
| Number of Bits | 8 | 12 |
| Voltage - Supply, Analog | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Voltage - Supply, Digital | 1.7V ~ 5.25V | 2.7V ~ 5.25V |
| Number of Inputs | 4 | 1 |
| Input Type | Single Ended | Single Ended |
| Configuration | MUX-S/H-ADC | S/H-ADC |
| Ratio - S/H:ADC | 1:1 | 1:1 |
| Number of A/D Converters | 1 | 1 |
| Architecture | SAR | SAR |
-
1. What is the main purpose of ADC?
The main purpose of ADC is to convert the input analog signal into a digital signal.
ADC, or analog-to-digital converter, is mainly used to convert continuously changing analog signals into discrete digital signals. The implementation process of ADC usually includes four steps: sampling, holding, quantization, and encoding.
-
2. What process converts analog to digital?
There are three basic processes for analog to digital conversion:
The first process is "sampling", which is to extract the sample value of the analog signal at equal intervals to turn the continuous signal into a discrete signal.
The second process is called "quantization", which is to convert the extracted sample value into the closest digital value to represent the size of the extracted sample value.
The third process is "encoding", which is to represent the quantized value with a set of binary digits. After these three processes, the digitization of the analog signal can be completed. This method is called "pulse encoding".
After the digital signal is transmitted to the receiving end, a restoration process is required, that is, the received digital signal is converted back to an analog signal so that it can be understood by the receiver. This process is called "digital-to-analog conversion", which reproduces it as sound or image. -
3. Why do we need analog-to-digital converters?
The reasons why we need analog-to-digital converters mainly include the following:
Digital system processing: Many computers and electronic devices are digital systems, which are more suitable for processing digital signals. Analog signals are difficult to process in digital systems, and after analog-to-digital conversion, the signals can be represented, stored and processed in digital form.
Noise immunity: Digital signals are more noise-resistant than analog signals. Digital signals can be protected and restored by means such as error correction codes, while analog signals are easily interfered by noise.
Accuracy: Digital signals are more accurate because they can be represented with higher resolution. Analog signals have accuracy limitations, and analog-to-digital conversion can improve the resolution of the signal.
Application scenarios: Analog-to-digital converters are widely used in many fields, including automatic control systems, audio and video processing, sensor interfaces -
4. When is ADC used?
ADC (Analog-to-Digital Converter) is widely used in a variety of scenarios, including but not limited to:
Sensor interface: For example, temperature sensors, pressure sensors, and light sensors, ADC converts analog voltages into digital signals for the use of digital thermometers, temperature control systems, barometers, air pressure sensing systems, light intensity detection and control systems.
Audio signal processing: In microphones, ADC converts analog audio signals into digital signals for digital audio processing, recording, and playback.
Medical equipment: Such as electrocardiograms (ECGs) and oximeters, ADC converts analog signals of ECG signals and blood oxygen saturation into digital signals for heart health monitoring and diagnosis and blood oxygen level monitoring.
Data acquisition system: In various applications that need to collect data from analog signals, ADC is used to convert analog signals into digital signals for storage, processing, and analysis.

