XRK799J93 Datasheet, PDF (6/10 Pages) Exar Corporation – INTELLIGENT DYNAMIC CLOCK SWITCH PLL CLOCK DRIVER

XRK799J93
INTELLIGENT DYNAMIC CLOCK SWITCH PLL CLOCK DRIVER
xr
REV. 1.0.1
AC CHARACTERISTICS (V_CC= 3.3 + 5%, T_A= -40°C TO +85°C) ^f
SYMBOL
PARAMETER
MIN
TYP
f_ref Input Reference Frequency ÷4 feedback
40
f_VCO PLL VCO Lock Range
160
f_MAX Output Frequency
Qa[1:0] 40
Qb[2:0] 80
f_refDC Reference Input Duty Cycle
25
t_pd Propagation Delay
CLKn to Ext_FB (SPO) ^c
CLKn to Q (Bypass)
-150
V_{PP Differential peak-to-peak input voltage} ^g
0.25
V_{CMR Differential input crosspoint voltage} ^h
V_CC-1.7
t_skew
Output-to-Output Skew
Within Qa[1:0] or Qb[2:0]
All outputs
Δ_per/cycle
Rate of change of periods
Qa[1:0] ^d
Qb[2:0] ^d
Qa[1:0] ^e
Qb[2:0] ^e
DC Output duty cycle
45
MAX
95
380
95
190
75
150
5
1.3
V_CC-0.3
50
80
50
25
400
200
55
UNIT
MHz
MHz
MHz
CONDITION
Locked
Qa output used
for feedback
%
ps
PLL_En=1
ns
PLL_En=0
V
V
ps
ps/
cycle
%
t_{jitter Cycle-to-cyle jitter, Standard deviation (RMS)}
t_{lock Maximum PLL lock time}
t_r/t_{f Output Rise/Fall time}
50
40
ps
@ f_ref =75MHZ
10
ms
700
ps
c. Static phase offset between the selected reference clock and the feedback signal.
d. Specification holds for a clock switch between two signals no greater than 400ps out of phase. Delta period change
per cycle is averaged over the clock switch excursion. (See Applications Information section for more detail)
e. Specification holds for a clock switch between two signals no greater than ±π out of phase. Delta period change per
cycle is averaged over the clock switch excursion.
f. PECL output termination is 50 ohms to VCC – 2.0V.
g. V_PP is the minimum differential input voltage swing required to maintain AC characteristic including SPO, device and
part-to-part skew. Applicable to CLK0, CLK1 and Ext_FB.
h. V_CMR is the crosspoint of the differential input signal. Normal operation is obtained when the crosspoint is within the
V_CMR range and the input swing lies within the V_PP specification. Violation of V_CMR or V_PP impacts the SPO, device
and part-to-part skew. Applicable to CLK0, CLK1 and Ext_FB.
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