YTD428 Datasheet, PDF (4/14 Pages) YAMAHA CORPORATION – DSU LSI for the ISDN Terminal Equipment

❒ DSU Configuration Example
YTD428 incorporates the circuit termination, line termination, T reference point interface and U
reference point interface functions on a single chip allowing the user to easily configure a DSU that
consumes small amount of power at a minimal cost. The user can select from the two types of
configurations. One is the general configuration in which a transformer is used at the T reference
point interface. The other is a configuration in which a TTL interface is used to directly connect to
the T reference point LSI.
s Configuration example of a general DSU
Various functions are incorporated on a single chip allowing the user to create a low power-consuming
product at a low cost.
Layer 3 info.
Bch data
T ref. pt.
YM7405 or
YTD410
for S/T ref. pt.
included driver/receiver
for S/T ref. pt.
RA / RB
TA / TB
YTD428
U ref. pt. driver
Call control
circuit
DSU
L1
L2
-4-