mpc9331 Integrated Device Technology, mpc9331 Datasheet - Page 9

• Manufacturer Part Number: mpc9331
• Description: 3.3v 1 6 Lvcmos Pll Clock Generator
• Manufacturer: Integrated Device Technology

IDT™ 3.3 V 1:6 LVCMOS PLL Clock Generator
Freescale Timing Solutions Organization has been acquired by Integrated Device Technology, Inc
MPC9331
3.3 V 1:6 LVCMOS PLL Clock Generator
Advanced Clock Drivers Devices
Freescale Semiconductor
unity reflection coefficient, to 2.6 V. It will then increment
towards the quiescent 3.0 V in steps separated by one round
trip delay (in this case 4.0 ns).
1.
At the load end, the voltage will double due to the near
3.0
2.5
2.0
1.5
1.0
0.5
Final skew data pending specification.
0
Figure 5. Single versus Dual Line
t
D
2
V
Z
R
R
V
= 3.8956
OutA
0
L
L
S
0
In
Termination Waveforms
= V
= 50 Ω || 50 Ω
= 36 Ω || 36 Ω
= 14 Ω
= 3.0 (25 ÷ (18+14+25)
= 1.31 V
4
S
(Z
0
Generator
Z = 50Ω
÷ (R
6
Pulse
Time (ns)
t
S
D
Figure 7. CCLK MPC9331 AC Test Reference for V
+R
= 3.9386
OutB
8
0
+ Z
0
))
10
Z
12
O
= 50Ω
R
T
= 50Ω
14
V
TT
MPC9931 DUT
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cause any false clock triggering; however, designers may be
uncomfortable with unwanted reflections on the line. To better
match the impedances when driving multiple lines, the
situation in should be used. In this case the series terminating
resistors are reduced such that when the parallel combination
is added to the output buffer impedance, the line impedance
is perfectly matched.
Since this step is well above the threshold region it will not
Figure 6. Optimized Dual Line Termination
MPC9331
Output
Buffer
14Ω
14Ω + 22Ω || 22Ω = 50Ω || 50Ω
Z
O
cc
= 50Ω
= 3.3 V
25Ω = 25Ω
R
R
R
T
S
S
= 50Ω
= 22Ω
= 22Ω
V
TT
Z
Z
O
O
= 50Ω
= 50Ω
MPC9331
NETCOM
MPC9331
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