TEA1110A is a low voltage versatile telephone transmission circuit with dialler interface. Its features include low DC line voltage operation down to 1.6V (excluding voltage drop over external polarity guard); voltage regulator with adjustable DC voltage for external circuit supply; symmetrical high impedance inputs (64 kΩ) for dynamic, magnetic or piezo-electric microphones; asymmetrical high impedance input (32 kΩ) for electret microphones; DTMF input with confidence tone; MUTE input for pulse or DTMF dialling; receiving amplifier for dynamic, magnetic or piezo-electric earpieces; AGC line loss compensation for microphone and earpiece amplifiers. Applications include line powered telephone sets, cordless telephones, fax machines, answering machines.
The Philips TEA1110A is a bipolar integrated circuit designed for fully electronic telephone sets, cordless telephones, fax machines, and answering machines. It performs all speech and line interface functions, including electronic switching between speech and dialling, and operates at line voltages down to 1.6 V DC.
The device features symmetrical high impedance inputs for dynamic, magnetic, or piezo-electric microphones and an asymmetrical input for electret microphones. It includes a receiving amplifier for earpieces, automatic gain control (AGC) for line loss compensation, and a mute function to select between speech and dialling modes. The IC also supports DTMF input with a confidence tone.
| Minimum DC line voltage | 1.6 V |
|---|---|
| Microphone input impedance | 64 kΩ |
| Electret microphone input impedance | 32 kΩ |
| Microphone amplifier voltage gain | 43.7 dB |
| Receiving amplifier voltage gain | 33 dB |
| DTMF input impedance | 20 kΩ |
| DTMF voltage gain | 25.3 dB |
| Package type | DIP14 |
It is suitable for line powered telephone sets, cordless telephones, fax machines, and answering machines.
When MUTE is LOW, the DTMF input is enabled and amplifiers are disabled; when HIGH, amplifiers are enabled and DTMF is disabled.