AS2534U

Overview

The AS2534U is a CMOS integrated circuit designed for basic electronic telephone sets. It integrates a line interface, speech circuit, dialler, and ringer in a single die with 28 pins. The device supports LD/MF dialing, 31-digit last number redial (LNR), and repeat dialing. It features electronic Rx volume control, microphone mute, and automatic line loss compensation. Operating range is 13 to 100 mA, extending to 5 mA with reduced performance. Supply voltage is 3.8V to 5V. It includes a 3-tone melody generator and ring frequency discrimination.

Feature Summary

• Integrated line interface with speech circuit and dialler
• Supports LD/MF dialing and mixed-mode operations
• Features 31-digit last number redial capability
• Includes programmable 3-tone melody generator

Applications

• Basic electronic telephone sets
• PABX compatible telephones
• Telephones requiring LNR functionality

Procurement Notes

Verify the specific suffix 'U' against official documentation to confirm package or temperature grade variations. Confirm pin compatibility with AS2533/36 series if substituting. Ensure supply voltage and line current requirements match the application design.

Selection Notes

Select AS2534U when direct memory keys are not required but indirect memories and repeat dialing are needed. Compare with AS2533/36 for direct memory options. Verify mode pin configuration for LD/MF selection. Check keyboard matrix requirements for VOL/+/- keys.

Part Context

Part of the AS253x family from ams AG (formerly austriamicrosystems). Pin-compatible variants include AS2533, AS2535, and AS2536. Designed for basic telephony applications with CMOS technology for low power consumption and EMI performance.

Replacement Considerations

AS2533, AS2535, AS2536 are pin-compatible variants within the AS253x family. Verify feature differences such as direct memory availability and repeat dialing support before substitution.