CS1238 – 24-bit Low-Power High-Precision Sigma-Delta ADC with Dual Differential Inputs and Temperature Sensor

CS1238 is a high-precision, low-power Sigma-Delta analog-to-digital converter (ADC) with integrated temperature sensor and crystal oscillator. It supports dual 24-bit no-missing-code differential input channels and offers selectable gain and output rates, making it ideal for accurate and versatile signal acquisition in industrial and medical applications.

The programmable gain amplifier (PGA) offers gain settings of 1, 2, 64, and 128 (default 128), and supports effective resolution (ENOB) up to 20.7 bits at 5V or 20.2 bits at 3.3V. The ADC supports four output data rates—10Hz, 40Hz, 640Hz, and 1.28kHz—selectable via an SPI interface. The integrated crystal oscillator eliminates the need for external clocking, while the built-in temperature sensor enables additional environmental data acquisition.

CS1238 communicates with a host MCU through a 2-wire SPI interface (SCLK, DRDY/DOUT) with speeds up to 1.1MHz. It also includes a power-down mode and internal short-circuit testing functionality for system reliability and energy efficiency.

🔧 Key Features:

• 24-bit no-missing-code Sigma-Delta ADC

• Dual differential input channels

• Programmable gain amplifier (PGA): 1, 2, 64, 128 (default: 128)

• Effective resolution (ENOB): 20.7 bits @5V, 20.2 bits @3.3V

• Output data rates: 10Hz, 40Hz, 640Hz, 1.28kHz (default: 10Hz)

• Peak-to-peak noise (PGA=128, 10Hz): 150nV

• INL < 0.0015%

• Integrated temperature sensor

• Integrated high-accuracy crystal oscillator

• Internal short detection function

• Low-power mode with power-down support

• 2-wire SPI interface (up to 1.1MHz)

📌 Typical Applications:

• Industrial process control systems

• Digital weighing scales

• Liquid and gas chemical analysis

• Blood analyzers and diagnostic equipment

• Smart transducer systems

• Portable measurement and data logging devices