U209B
| Model | U209B |
| Description | Monolithic Integrated Feature Phone Circuit |
| PDF file | Total 34 pages (File size: 675K) |
| Chip Manufacturer | ATMEL |
U4090B
VL
GT
MICO
TIN
INLDT
TLDT
STO
VL
ZL
VBG
–
+
TXA
Zint
SAO
AFS
control
Max
att.
AGA
GSA
SAI
SAI
TLDR
–
VBG
+
INLDR
RECO1
GR
RECIN
STIS
STO
STN
94 8059
Figure 6. Integration of acoustic feedback suppression circuit into the speech circuit environment
A detailed diagram of the AFS (acountic feedback
suppression) is given in figure 10. Receive and Transmit
signals are first processed by logorithmic rectifiers in
order to produce the envelopes of the speech at TLDT and
RLDT. After amplification a decision is made by the
differential pair, which direction should be transmitted.
TELEFUNKEN Semiconductors
Rev. C1, 28-Oct-96
11 (34)
Preliminary Information
