STMicroelectronics TEA7540
TEA7540 is background noise level discrimination in each way. The IC stores the background sound level with a long time constant (3 to 5 seconds depending on an external RC) and compares it with the incoming signal in order to distinguish a useful signal (speech) from the background noise. This background noise memorization is also used to compensate the noise in each mode before signal comparison: the noise level in each mode is sub3/12 TEA7540 stracted from the incoming signal before the comparison.| Part No. | TEA7540 |
|---|---|
| Datasheet | TEA7540 Download |
| Manufacturer |  STMicroelectronics |
| Description | HANDSFREE CONTROLLER |
| Buy | Stock & Price |
DESCRIPTION
This 28 pins IC is an innovative approach to quality handsfree telephone sets. It results from an extensive research on speech signal. PIN CONNECTION (top view) GND CS OUTE ATTE HYST1 HYST2 TIM CCE CE3 CE2 CE1 MICOUT INE VREF 1 2 3 4 5 6 7 8 9 10 11 12 13 14 D93TL005 28 27 26 25 24 23 22 21 20 19 18 17 16 15 V+ IREF OUTR ATTR ATR VOL AMP SUP AMP IN CCR CR3 CR2 CR1 RECOUT INR July 1998 T 1/12 is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without TEA7540 BLOCK DIAGRAM 2/12 TEA7540 PIN FUNCTION N° 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Name GND CS OUTE ATTE HYST1 HYST2 TIM CCE CE3 CE2 CE1 MICOUT INE Vref INR RECOUT CR1 CR2 CR3 CCR AMP IN AMP SUP VOL ATR ATTR OUTR Iref V+ Ground Chip Select Transmit Attenuator Output Transmit Attenuator Input Transmit Channel Hysteresis Receive Channel Hysteresis RC Timer Time Constant of the Transmit Signal Compressor Transmit Background N...
