DS21FT44/DS21FF44
4x3 Twelve Channel E1 Framer
4x4 Sixteen Channel E1 Framer
www.dalsemi.com
FEATURES
·
Sixteen (16) or twelve (12) completely
independent E1 Framers in one small 27mm
x 27mm Package
Each Multi-Chip Module (MCM) contains
either four (FF) or three (FT) DS21Q44 die
Each quad framer can be concatenated into a
single 8.192MHz Backplane Data Stream
IEEE 1149.1 JTAG-Boundary Scan
Architecture
·
DS21FF44 and DS21FT44 are pin
compatible with DS21FF42 and DS21FT42,
respectively to allow the same footprint to
support T1 and E1 applications
300–pin MCM BGA 1.27 mm pitch package
(27mm X 27mm)
Low power 3.3V CMOS with 5V tolerant
input & outputs
·
·
·
·
·
1. MULTI-CHIP MODULE (MCM) DESCRIPTION
The Four x Four and Four x Three MCMs offer a high density packaging arrangement for the DS21Q44
E1 Enhanced Quad Framer. Either three (DS21FT44) or four (DS21FF44) silicon die of these devices is
packaged in a Multi-Chip Module (MCM) with the electrical connections as shown in Figure 1-1.
All of the functions available on the DS21Q44 are also available in the MCM packaged version.
However, in order to minimize package size, some signals have been deleted or combined. These
differences are detailed in Table 1-1. In the Four x Three (FT) version, the fourth quad framer is not
populated and hence all of the signals to and from this fourth framer are absent and should be treated as
No Connects (NC). Table 2-1 lists all of the signals on the MCM and it also lists the absent signals for
the Four x Three.
The availability of both a twelve and a sixteen-channel version allow the maximum framer density with
the lowest cost.
1 of 110
120601
DALLAS [ DALLAS SEMICONDUCTOR ]
