THS788 Datasheet, PDF (31/43 Pages) Texas Instruments – QUAD-CHANNEL TIME MEASUREMENT UNIT (TMU)

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THS788
LVDS
Driver
THS788
SLOS616B – MARCH 2010 – REVISED JUNE 2011
50 W Tranmission Line
Equal Length
100
RT
LVDS
Receiver
1.28 V Ref.
+ _A1
–
Figure 11. Typical Output Connection to the THS788
VCC
R
R
S0391-01
2.5 nH
25
Bond Wire
OUT
3k
3k
1 pf
VCC
0.1 pf
Bond Pad
0.5 pf
Package
2.5 nH
25
Bond Wire
OUT
D
1 pf
0.1 pf
0.5 pf
Bond Pad
Package
4 mA
–
A2
+
0.4 V Ref.
Figure 12. Simplified Schematic of the LVDS Output Driver
S0392-01
TIME MEASUREMENT
Time measurements in the THS788 follow the timing of Figure 13. This diagram illustrates that time
measurements are valid as long as events do not happen at speeds higher than 200 MHz. If an event happens
at less than 5 ns from the previous one, then this event is ignored. The same applies to the SYNC signal. Even
though the minimum period is 5 ns, the pulse duration of both Event and SYNC signals can be as low as 200 ps.
Copyright © 2010–2011, Texas Instruments Incorporated
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