Datasheet
MAX3982
SFP Copper-Cable Preemphasis Driver
_______________________________________________________________________________________ 3
Note 1: Guaranteed by design and characterization.
Note 2: PE1 = PE0 = 1 for maximum preemphasis, load is 50Ω ±1% at each side, and the pattern is 0000011111 at 1Gbps.
Note 3: Measured at point B in Figure 2 using 0000011111 at 1Gbps. PE1 = PE0 = 0 for minimum preemphasis. For transition time,
the 0% reference level is the steady-state level after four zeros, just before the transition. The 100% reference level is the
maximum voltage of the transition.
Note 4: Tested with CJTPAT, as well as this pattern: 19 zeros, 1, 10 zeros, 1010101010 (D21.5 character), 1100000101 (K28.5+
character), 19 ones, 0, 10 ones, 0101010101 (D10.2 character), 0011111010 (K28.5 character).
Note 5: Cables are unequalized, Amphenol Spectra-Strip 24AWG. Residual deterministic jitter is the difference between the source
jitter at point A, and load jitter at point D in Figure 2. The deterministic jitter at the output of the transmission line must be
from media-induced loss and not from clock-source modulation.
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.0V to +3.6V, T
A
= 0°C to +85°C. Typical values are at T
A
= +25°C and V
CC
= +3.3V, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX
UNITS
EQUALIZER AND CABLE DRIVER SPECIFICATIONS
Input Swing
Measured differentially at point A of Figure
2 (Note 1)
600 2000
mV
P-P
Input Resistance Measured differentially 85
100 115
Ω
Input Return Loss 100MHz to 2GHz (Note 1) 10 dB
TX_DISABLE = low,
OUTLEV = high
1450 1800
TX_DISABLE = low,
OUTLEV = low
1000 1350
Differential Output Swing
Measured
differentially at point
B of Figure 2
(Notes 1, 2)
TX_DISABLE = high
40
mV
P-P
Common-Mode Output
(OUT+) + (OUT-), measured at point B of
Figure 2; TX_DISABLE = low, OUTLEV =
high (Notes 1, 2)
60
mV
P-P
Output Resistance OUT+ or OUT- to V
CC
, single ended 42 50 58 Ω
Output Return Loss 100MHz to 2GHz (Note 1) 10 dB
Output Transition Time t
r
, t
f
20% to 80% (Notes 1, 3) 50 80 ps
Random Jitter (Notes 1, 3) 1.6
ps
RMS
PE1 PE0
00
2
01
4
10
8
Output Preemphasis See Figure 1
11
14
dB
Source to IN
OUT to Load PE1 PE0
1m, 24AWG 0 0
5m, 24AWG 0 1
10m, 24AWG 1 0
Residual Output Deterministic
Jitter at 1.0625Gbps to
2.125Gbps (Notes 1, 4, 5)
6 mil
FR4 ≤ 10in
15m, 24AWG 1 1
0.10 0.15
UI
P-P
Source to IN
OUT to Load PE1 PE0
1m, 24AWG 0 0
5m, 24AWG 0 1
10m, 24AWG 1 0
Residual Output Deterministic
Jitter at 4.25Gbps (Notes 1, 4, 5)
6 mil
FR4 ≤ 10in
15m, 24AWG 1 1
0.15 0.20
UI
P-P