The part you are referring to, "ADS1118IDGSR," is a part from Texas Instruments (TI). The ADS1118 is a 16-bit Analog-to-Digital Converter (ADC) with an I2C interface , integrated programmable gain amplifier (PGA), and is typically used for high-resolution measurements in sensors or other analog signal processing applications.
Package and Pin Specifications
The ADS1118IDGSR comes in the QFN-16 (Quad Flat No-lead) package. This means it has 16 pins that need to be soldered to a PCB (Printed Circuit Board) in a specific configuration.
Pinout and Pin Functions
Below is a detailed explanation of the 16 pins for the ADS1118IDGSR:
Pin Number Pin Name Function Description 1 VDD Power supply input (positive voltage), typically 2.0V to 5.5V 2 SDA I2C data line for communication with the microcontroller (bidirectional) 3 SCL I2C clock line for communication with the microcontroller 4 ADDR0 Address pin 0 for I2C addressing (connect to ground for default address) 5 ADDR1 Address pin 1 for I2C addressing (connect to ground for default address) 6 ALERT/RDY Alert/Ready pin (output): can signal when conversion is complete or error is detected 7 GND Ground pin (0V), connected to the common ground of the system 8 A0 Input channel 0 for analog signal (single-ended input, differential configuration) 9 A1 Input channel 1 for analog signal (single-ended input, differential configuration) 10 A2 Input channel 2 for analog signal (single-ended input, differential configuration) 11 A3 Input channel 3 for analog signal (single-ended input, differential configuration) 12 REF Reference input pin for internal reference voltage (typically tied to ground) 13 VSS Ground connection (also called "AGND" in some datasheets) 14 VDD Power supply input (positive voltage, same as Pin 1) 15 IN+ Positive input for differential measurements (combined with IN-) 16 IN- Negative input for differential measurements (combined with IN+)Circuit Principle
The ADS1118 functions as a high-precision, low-power, 16-bit ADC with a built-in PGA. It converts analog signals into digital signals for use in a microcontroller or other digital logic circuits. The ADC operates by taking the difference between two input signals (differential input) or a single-ended signal (relative to ground).
The SDA and SCL pins are used for communication with the host microcontroller over the I2C protocol. The ALERT/RDY pin can be used to signal when the conversion process is complete. The device also includes programmable input channels and an internal reference, providing flexibility for different sensor and measurement applications.
FAQ for ADS1118IDGSR
Q: What is the operating voltage range for ADS1118IDGSR? A: The operating voltage range is 2.0V to 5.5V.
Q: What is the resolution of the ADC? A: The resolution is 16 bits, providing 65,536 discrete values.
Q: How many input channels does the ADS1118 support? A: The ADS1118 supports 4 input channels (A0, A1, A2, A3) for single-ended or differential measurements.
Q: What is the data rate of the ADS1118? A: The data rate can be set from 8 SPS to 860 SPS (Samples per second).
Q: What is the power consumption of the ADS1118? A: The typical current consumption is around 150 µA during operation.
Q: How does the ALERT/RDY pin function? A: The ALERT/RDY pin signals when a conversion is complete or if an alert condition is met (e.g., over-range).
Q: Can the ADS1118 operate on a single-ended input? A: Yes, it can operate with single-ended inputs, measuring the voltage difference between any of the input channels and ground.
Q: Is the reference voltage internal or external? A: The ADS1118 uses an internal reference voltage, but it also has the option to use an external reference voltage for greater accuracy.
Q: What is the I2C address for ADS1118? A: The default I2C address is determined by the address pins (ADDR0, ADDR1). Typically, it is 0x48, but it can be adjusted by connecting these pins to logic levels.
Q: What is the significance of the SDA and SCL pins? A: These pins are used for I2C communication, with SDA carrying data and SCL providing the clock signal for data transfer.
Q: How can I configure the ADS1118 for higher resolution? A: The ADS1118 has a programmable gain amplifier (PGA) that can be configured to increase the effective resolution for smaller input voltage ranges.
Q: What is the function of the REF pin? A: The REF pin is used to input a reference voltage for the ADC. It is typically tied to ground for a single-ended measurement.
Q: Can I use the ADS1118 for differential voltage measurements? A: Yes, the ADS1118 can measure the difference between two input channels (e.g., IN+ and IN-) for differential measurements.
Q: What is the typical output format of the ADC? A: The output is a 16-bit binary value, which represents the digital equivalent of the analog input signal.
Q: What is the maximum sampling rate for the ADS1118? A: The maximum sampling rate is 860 samples per second (SPS).
Q: Is the ADS1118 suitable for low-power applications? A: Yes, it is designed for low-power applications, consuming minimal current during operation.
Q: How accurate is the ADS1118? A: The ADS1118 offers a typical accuracy of ±0.5 LSB, with a typical gain error of 0.05%.
Q: Can the ADS1118 be used for temperature sensing? A: Yes, the ADS1118 can be used for temperature sensing when paired with a thermistor or temperature sensor.
Q: How can I change the I2C address of the ADS1118? A: The I2C address can be changed by configuring the ADDR0 and ADDR1 pins to different logic levels.
Q: What is the temperature range for the ADS1118? A: The operating temperature range is from -40°C to +125°C, making it suitable for a wide range of applications.
This detailed explanation covers the main aspects of the ADS1118IDGSR, including the pinout, its function, usage, and some frequently asked questions. Let me know if you'd like more detailed information or additional clarifications!
