ST20138
Unicorn II
PCI/USB ADSL CHIPSET: ST70138 + MTC20174
FOR ULTRA LOW COST ADSL MODEM
DATA BRIEF
The Unicorn II chipset consists of the digital
ST70138 chip and the MTC20174 analog front
end.
1 DESCRIPTION
The Unicorn II chipset is designed to simplify the
development of low-cost ADSL CPE modems for
Windows, Mac and Linux based environments and
enables manufacturers to achieve a very compet-
itive production cost. Due to its controller-less ar-
chitecture and particularly the advantage that it
does not require an external SDRAM in its E-BOM,
the total cost of the external components needed
in the modem is the best in its class. With a low
component count of less then 140 external compo-
nents and small form factor packages, the Unicorn
II easily fits on a standard 2 layer single sided PCB
with small dimensions which contributes signifi-
cantly to further lowering overall system costs. To-
gether with its low power consumption, high-
speed performance up to 8 Mbps and customiz-
able complete software driver packages, the Uni-
corn II is the ideal choice for USB and PCI based
ADSL modems.
The ST70138 is supplied in two packages,
TQFP144 and LBGA80. The ST70138T packaged
in TQ144 is a pin-to-pin compatible version of the
ST70137 enabling manufacturers to benefit direct-
ly from the cost and performance advantages that
the ST70138 brings.
The TQ144 flavor brings out both the USB and PCI
interfaces. Supplied in a compact USB-only
LBGA80 package, the ST70138B brings addition-
al cost advantages to new designs.
The MTC20174 Analog Front End (AFE) with inte-
grated line driver is designed for DMT based
ADSL CPE modems compliant with ANSI T1.413
issue 2, ITU G.992.1 (G.dmt) and ITU G.992.2
(G.lite), for Annex A, B and C.
Figure 1. Chipset Architecture Overview
MTC20174
AFE
ST70138
DMT/ATM
Line Interface
USB
PCI
Phone Line
EEPROM
(0-16KB)
Optional
PC/Mac
Rev. 1
1/6
September 2004
This is preliminary information on a new product foreseen to be developed. Details are subject to change without notice.