onsemi SCV431BSN1T1G: Key Features and Application Circuit Design

The onsemi SCV431BSN1T1G is a high-performance, ultra-low bias current shunt voltage reference, designed to deliver exceptional accuracy and stability for a wide range of precision analog applications. This component is critical in systems where a stable voltage benchmark is paramount, ensuring the integrity of measurements and conversions.

A standout feature of this device is its extremely low operating current, which can be as low as 55 µA. This makes it exceptionally suitable for battery-powered and portable equipment where power conservation is a primary design constraint. Furthermore, it offers a initial accuracy of ±0.5% and a low temperature coefficient, ensuring stable output voltage (1.24V) across a wide operating temperature range. Its small SOT-23 package also makes it ideal for space-constrained PCB designs.

A primary application circuit for the SCV431BSN1T1G is as a simple, precise voltage reference for an analog-to-digital converter (ADC). The basic design involves connecting the anode to ground and the cathode to the supply voltage through a current-limiting resistor. The output voltage is taken from the cathode pin. The value of the series resistor (\(R_s\)) is crucial and is calculated based on the supply voltage (\(V_{supply}\)) and the desired operating current (\(I_{op}\)) using the formula:

\[ R_s = (V_{supply} - V_{ref}) / I_{op} \]

A bypass capacitor of 100nF to 1µF placed close to the cathode pin is highly recommended to minimize noise and improve stability. For applications requiring higher output voltages, the device can be easily integrated with an operational amplifier in a non-inverting configuration.

ICGOODFIND: The onsemi SCV431BSN1T1G is an outstanding solution for designers seeking a compact, accurate, and ultra-low-power voltage reference. Its robust performance in demanding environmental conditions and simple integration make it a superior choice for enhancing the precision of portable instrumentation, data acquisition systems, and power management circuits.

Keywords: Shunt Voltage Reference, Ultra-Low Power, High Accuracy, Precision Analog, Battery-Powered Devices.