TEA7092 ST Microelectronics, Inc., TEA7092 Datasheet - Page 14

• Manufacturer Part Number: TEA7092
• Description: Telephone Analog Front End
• Manufacturer: ST Microelectronics, Inc.

TEA7092
MICROCONTROLLER INTERFACE (continued)
Serial Bus Interface (data and clock)
The serial bus uses 7 bits, a standard 8 bit word
can be sent, the TEA7092 take care only of the
seven first bits.
The different codes are :
- The ring start up code
- The ring frequency control code
- The mode codes :
- The operating codes (these codes are used un-
- The data codes (DTMF, sinus wave, ring fre-
- The configuration codes (those codes are "flip-
Figure 8 : 7 Bit Codes Data and Clock Input Timing
14/24
der each code mode) :
quency, error beep frequency codes) :
These data codes are stored inside the TEA7092
and are used as soon as an operating code is
sent, dialing, error beep, sine wave or ring melody
control or ring start up code.
flop” codes) :
Ik Data
Handset mode
Group listening mode
Handsfree mode
Speech
Dialing
Microphone mute
Earphone/Microphone mute
Error beep
Sine wave high frequency
Sine wave low frequency
AGC/no AGC
No mask / mask
ata
Datas will change during Clk = 1
Synchro
t1
t3
t2
a0
t1 = t2 = t4 = t5 = 1µs
t3 = 2µs
a1
a2
- The loudspeaker level control codes
- The reset code to inialize the TEA7092 and to set
- The Init code to initialize the TEA7092, software
- The start up condition of the TEA7092 is :
For instance : The first time that the +6dB code is
sent, the receive gain increases of +6dB. If it is sent
again, the receive gain goes back to normal value.
the reset output to "0" low logic level
initialization to set the TEA7092 in the start up
condition.
Normal gain/normal gain +6dB, on receive
channel
Two sidetone network/one sidetone network
Squelch/No squelch
Line current variation initialization (No trans-
fer/Transfer)
Minus 21dB in Ring Mode
Minus 6dB in Sending Mode
Oscillator Stand-by
Handset mode.
Speech.
No mask.
AGC in transmit and receive channels.
Normal gain on receive channel.
Squelch on transmit channel.
Two sidetone networks.
No transfer.
Oscillator ON.
PON line threshold current : 12mA.
Anti-acoustic feed-back attenuation : 15dB.
a3
t4
a4
t5
a5
a6