XRK49911 Datasheet, PDF (5/12 Pages) Exar Corporation – 3.3V HIGH-SPEED (110 MHZ) PROGRAMMABLE SKEW CLOCK BUFFER

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REV. 1.0.1
XRK49911
3.3V HIGH-SPEED (110 MHZ) PROGRAMMABLE SKEW CLOCK BUFFER
FIGURE 3. TYPICAL OUTPUTS WITH FB_IN CONNECTED TO A ZERO-SKEW OUTPUT
SELA[1:0]
SELB[1:0]
(N/A)
LL
LM
LH
ML
MM
MH
HL
HM
HH
(N/A)
(N/A)
(N/A)
FB_IN
SELC[1:0] ^CLKIN
SELD[1:0]
LM
LH
(N/A)
ML
(N/A)
MM
(N/A)
MH
(N/A)
HL
HM
LL/HH
-6t_U
-4t_U
-3t_U
-2t_U
-1t_U
0t_U
+1t_U
+2t_U
+3t_U
+4t_U
+6t_U
DIVIDED
HH(D) INVERT
PLL_BYPASS
The PLL_BYPASS input is a tri-level input. In normal system operation, this pin is connected to ground.
In normal operation (tied LOW) all outputs will function based only on the connection of their own function
select inputs (SELx[1:0]) and the waveform characteristics of the PLL.
If the PLL_BYPASS input is forced to its MID or HIGH state the device will operate in PLL bypass mode, with
the phase locked loop disconnected, and CLKIN waveforms will directly control all outputs. Relative output to
output timing is controlled by the SELx[1:0], the same as in normal mode.
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