■ DESCRIPTION

The FUJITSU MB86437 is an AIU (audio interface unit) LSI for +3 V single-power source digital telephone devices, manufactured using CMOS process technology. The codec transmission filter characteristics meet G.712 standards, and can handle input and output in A-Law, µ-Law and linear conversion modes. The MB86437 also contains the necessary DTMF, microphone and receiver amps for telephone devices.

■ FEATURES

• +3 V single power supply

• Low power consumption: muting settings for each operating mode

Normal operation : 5.0 mA TYP

Standby mode : 0.5 µA TYP

• On-chip codec filter meets G.712 standards

• Selection of codec companding law (A-law, µ-law, 14 bit linear)

• On-chip low-noise microphone amp (2-channel) (0 to 35 dB amplification)

• On-chip receiver speaker amps (32 Ω BTL type: 10 mW MIN)

• On-chip earphone speaker amps (32 Ω single type: 5 mW MIN)

• On-chip electronic volume gain adjustments (sending, receiving, tone)

• On-chip accessory input/output circuits

• DTMF generator function

• Service tone generation

• CMOS compatible input/output