AS1974

Overview

The AS1974 is a quad low-voltage comparator manufactured by ams-OSRAM USA INC. It operates on single supplies from 2.5V to 5.5V or dual supplies of ±1.25V to ±2.75V. The device features a push/pull output stage capable of sourcing and sinking up to 8mA, ensuring rail-to-rail output swings. Key electrical characteristics include a typical quiescent supply current of 36µA (max 64µA) at 5V, a propagation delay of 300ns to 400ns, and an internal hysteresis of 3mV. The input common-mode voltage range extends 250mV beyond the supply rails, and the package is a 14-pin TSSOP.

Feature Summary

• Quad configuration with CMOS push/pull output drivers
• Internal hysteresis for clean switching
• Rail-to-rail output swing capability
• Extended common-mode input voltage range

Applications

• Battery-powered systems
• Zero-crossing detectors
• Window comparators
• Logic-level translators
• Threshold detectors and discriminators

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm the delivery form, as standard tubes and tape-and-reel options exist for this model. Ensure the component source matches the original austriamicrosystems AG manufacturing lineage now under ams AG. Cross-reference the pinout and marking codes provided in the datasheet to validate authenticity upon receipt.

Selection Notes

Select the AS1974 when a quad comparator solution is required within space-constrained designs utilizing a 14-pin TSSOP package. This model is appropriate for applications demanding low power consumption alongside high-speed signal processing capabilities. Consider the push/pull output architecture if direct driving of loads without external pull-up resistors is necessary compared to open-drain alternatives.

Part Context

The AS1974 belongs to the AS1970–AS1975 series of low-voltage comparators originally developed by austriamicrosystems AG. These devices are designed for 3V and 5V logic applications, offering minimal propagation delay and low supply current. The series includes single, dual, and quad variants with either push/pull or open-drain outputs, catering to diverse interface requirements in portable electronics and power management systems.

Replacement Considerations

Direct functional substitutes within the same family include the AS1975, which offers identical quad configuration but utilizes an open-drain output stage instead of push/pull. Designers must account for the output driver differences when swapping between these models to ensure compatibility with existing circuit load requirements.