FMS3818 Datasheet, PDF (10/13 Pages) Fairchild Semiconductor – Triple Video D/A Converter 3 x 8 bit, 180 Ms/s

FMS3818
PRODUCT SPECIFICATION
U1
FMS3818
IOG ³²
29
IOB
33
IOR
W1
COAX
R1
75
W2
COAX
R2
75
W3
COAX
R3
75
L1
220nH
L2
220nH
L3
220nH
R4
R5
R6
75
75
75
Figure 3. Schematic, FMS3818 Transition Time Sharpening Circuit
A 220 nH inductor trims the performance of a 4 ft cable,
quite well. In Figures 4 through 7, the glitch at 12.5 ns, is due
to a reflection from the source. Not shown, are smaller
glitches at 25 and 37.5 ns, corresponding to secondary and
tertiary reflections. Inductor values should be selected to
match the length and type of the cable.
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-5.00
0.00
5.00
10.00
15.00
Time (ns)
Figure 4. Unmatched tR.
20.00
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-5.00
0.00
5.00
10.00
15.00
Time (ns)
Figure 6. Unmatched tF.
20.00
10
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-5.00
0.00
5.00
10.00
15.00
Time (ns)
Figure 5. Matched tR.
20.00
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-5.00
0.00
5.00
10.00
15.00
Time (ns)
Figure 7. Matched tF.
20.00
REV. 1.2.2 11/11/01