KA431ZTA

Overview

The KA431ZTA is a three-terminal programmable shunt regulator manufactured by Fairchild Semiconductor. It functions as an adjustable voltage reference with an internal 2.5V reference. The output voltage is programmable between approximately 2.5V and 36V using two external resistors. Key electrical parameters include a typical dynamic output impedance of 0.2Ω, a sink current capability ranging from 1.0mA to 100mA, and a full-range temperature coefficient of 50ppm/°C. The device operates within a temperature range of -25°C to 85°C and is housed in a TO-92 package.

Feature Summary

• Programmable output voltage settable via two external resistors
• Temperature compensated for stable operation across the rated range
• Fast turn-on response characteristic suitable for zener diode replacement

Applications

• Precision voltage references in power supply circuits
• Linear regulators requiring adjustable output thresholds
• Comparator applications utilizing sharp turn-on characteristics

Procurement Notes

Verify the manufacturer designation carefully, as Fairchild Semiconductor has undergone integration with ON Semiconductor. Ensure the specific suffix matches the required package and tolerance specifications. Confirm RoHS compliance status and check for any obsolescence notices or lifecycle changes associated with the legacy Fairchild product line before finalizing procurement.

Selection Notes

Select this component when a low-cost, adjustable shunt regulator is required for industrial temperature ranges. The TO-92 through-hole package facilitates easy prototyping and manual assembly. Consider the 100mA maximum sink current limit for load requirements and ensure the external resistor network supports the desired voltage setting within the 36V maximum operating limit.

Part Context

The KA431 series belongs to the family of programmable shunt regulators, serving as a versatile alternative to fixed Zener diodes. Manufactured originally by Fairchild Semiconductor, these devices utilize a bandgap reference architecture to maintain thermal stability. The KA431ZTA specifically denotes the standard version packaged in a TO-92 case, widely used in general-purpose analog and power management designs.

Replacement Considerations

Compatible substitutes include the TL431 and LM431A, which share identical pinouts and functional specifications. Verify that replacement parts support the same TO-92 package and meet the required 50ppm/°C temperature coefficient for equivalent performance.