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Communication ICs

Speech network

BA6566 / BA6566F / BA6566FP

The BA6566, BA6566F, and BA6566FP are speech network ICs which possess the basic functions required for handset

communications. In addition to amplifying signals from a transmitter and sending them to a telephone line, they amplify

only reception signals from a telephone line and drive the receiver. They also compensate for fluctuation in the volume

at which signals are transmitted and received, caused by the length of the telephone line (AGC).

FApplications

Telephones and telephone equipment

FFeatures

1) Can accommodate both dynamic and piezoelectric

receivers, simply by changing the circuit constant for

a wide dynamic reception range.

2) Automatic gain control (AGC) is used, based on the

transmission and reception telephone line current,

for easier compliance with communications stan-

dards.

3) Erroneous operation caused by high-frequency elec-

trical wave interference is minimized.

4) An HSOP package is used, eliminating the need for

an attached transistor to dissipate heat. This means

that a common circuit can be shared when a DIP

package is used (BA6566FP).

FBlock diagram