AS2524BT

Overview

The AS2524BT is a CMOS integrated circuit designed for enhanced handsfree feature phones with CallerID and extended displays. It incorporates DC and AC line adaptation, speech circuits with softclipping, and line loss compensation for handset and handsfree operation. The device interfaces with standard diallers via a parallel interface on the AS2524 variant. Key electrical parameters include an operating current of 6 mA (typical) in speech mode and 10 mA in handsfree mode. Transmit gains are +37 dB (handset) and +46 dB (handsfree), while receive gain is +7.5 dB (handset) and +34 dB (handsfree). The supply voltage range supports operation from 15 mA to 100 mA.

Feature Summary

• Integrated DC and AC line adaptation with synthesized AC-impedance of 1000 ohms
• Enhanced voice switching with background noise monitoring and dual softclipping capabilities
• Loudspeaker amplifier support for loudhearing and handsfree modes
• Parallel interface compatibility with common Taiwanese dialers

Applications

• Enhanced handsfree feature phones with CallerID
• Devices requiring extended display integration
• Interfaces with common Taiwanese dialers

Procurement Notes

Verify the specific suffix 'T' indicates the SOIC28 plastic surface mounted package with 28 leads. Confirm that the AS2524B variant includes permanently activated Line Loss Compensation (LLC high) compared to the standard AS2524 which lacks LLC activation. Ensure the design utilizes the parallel interface logic levels defined for the AS2524 family rather than the serial interface used by the AS2523.

Selection Notes

Select the AS2524BT when a parallel interface is required instead of the serial interface found on the AS2523. Choose this model over the AS2524 if permanent Line Loss Compensation (LLC high) is needed for line currents between 45mA and 75mA. Consider the reduced performance operating range down to 5mA if power consumption is critical, noting that the device enters power down mode below 5mA.

Part Context

The AS2524BT belongs to the AS2523/24 series developed by austriamicrosystems AG (now ams AG). These devices share the same silicon die but differ in interface type and feature configuration. The AS2524 series specifically targets markets using standard parallel diallers, offering a cost-effective solution for handsfree telephony applications without the complexity of serial programming required by the AS2523.

Replacement Considerations

Public confirmed substitute part numbers: AS2524, AS2524B.