AS2535

Overview

The AS2535 is a CMOS integrated circuit designed for high-performance electronic telephones with basic features. It incorporates a line interface, speech circuit, dialler, and ringer in a single-chip architecture. The device supports LD/MF dialing, 12 direct memory keys, and Last Number Redial (LNR) with a 31-digit capacity. Operating voltage ranges from 3.8V to 5V, with a typical supply current of 4mA. It operates within a temperature range of -25°C to +70°C and is available in a 28-pin SOIC package.

Feature Summary

• Integrated line interface with electronic volume control and microphone mute
• Supports LD/MF dialing and mixed-mode dialing capabilities
• Includes 12 direct memory keys and 31-digit Last Number Redial function
• Features a 3-tone melody generator with programmable ring frequency discrimination

Applications

• Electronic telephone sets with basic features
• Telecom interface circuits requiring single-chip integration
• PABX compatible telephony systems

Procurement Notes

Verify component authenticity through authorized channels as the part is marked as obsolete. Confirm pin compatibility with existing designs since the AS253x family shares pinouts. Check for specific bond options that define the AS2535 variant features. Ensure environmental compliance requirements are met before procurement.

Selection Notes

Select the AS2535 when 12 direct memory keys are required without repeat dialing functionality. Compare against AS2533/36 if indirect memories or repeat dialing are needed instead. Verify keyboard matrix connections match the specific AS2535 layout provided in the datasheet. Ensure external components support the required impedance and line loss compensation settings.

Part Context

The AS2535 belongs to the AS253x family of multi-standard CMOS telephone ICs manufactured by ams OSRAM AG. This family includes variants like AS2533, AS2534, and AS2536, which differ primarily in memory configurations and dialing features. All members share the same 28-pin package and core functional blocks.

Replacement Considerations

Public confirmed substitute part numbers: AS2535UT-T.