AS2533

Overview

The AS2533 is a CMOS integrated circuit designed for high-performance electronic telephones with basic features. It integrates a line interface, speech circuit, dialler, and ringer into a single chip. The device supports LD/MF dialing, mixed-mode dialing, and offers 4 direct memories and 10 indirect memories. It operates within a supply voltage range of 3.8V to 5V and draws 3mA in speech mode. The IC is available in a 28-pin SOIC package or as a die.

Feature Summary

• Integrates line interface, speech circuit, dialler, and ringer functions
• Supports LD/MF dialing and mixed-mode dialing capabilities
• Includes 4 direct memory keys and 10 indirect memory keys
• Features electronic volume control and microphone mute

Applications

• Electronic telephone sets with basic features
• PABX systems requiring sliding cursor procedure
• Telecom interfaces requiring LNR functionality

Procurement Notes

Verify the specific revision level and manufacturer documentation when sourcing this component. Confirm pin compatibility and bond options if selecting from the AS253x family. Ensure the supplier provides official datasheets to validate electrical characteristics and functional descriptions against the original austriamicrosystems/ams AG specifications.

Selection Notes

Select the AS2533 when four direct memory keys and ten indirect memory keys are required. Choose this model over the AS2536 if repeat dialing functionality is not needed. Consider the AS2535 if twelve direct memory keys are preferred instead of indirect storage. Verify PTT requirements for impedance and signaling modes before finalizing the selection.

Part Context

The AS2533 belongs to the AS253x family of multib-standard CMOS telephone ICs manufactured by ams AG (formerly austriamicrosystems). This family includes variants like the AS2534, AS2535, and AS2536, which share pin compatibility but differ in memory configurations and feature sets such as repeat dialing and direct memory counts.

Replacement Considerations

The AS2536 is a pin-compatible alternative within the same family. It differs by offering repeat dialing functionality, whereas the AS2533 does not support this feature. Both models provide identical direct and indirect memory capacities.