Rainbow Electronics MAX3645 - Manual (Page 3)

MAX3645
+2.97V to +5.5V, 125Mbps to 200Mbps Limiting
Amplifier with Loss-of-Signal Detector
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Note 1: Between sensitivity and overload, the output amplitude is >95% of the fully limited amplitude and all AC specifications are met.
Note 2: Guaranteed by design and characterization.
Note 3: Noise is derived from BER measurement.
Note 4: The data input transition time is controlled by a 4th-order Bessel filter with f
-3dB
= 0.75 × data rate.
Note 5: PWD = [(width of wider pulse) - (width of narrower pulse)] / 2, measured with 155Mbps 0011 pattern.
Note 6: All LOS specifications are measured using a 155Mbps 2
23 - 1 PRBS pattern.
Note 7: The signal at the input is switched between two amplitudes, SIGNAL_ON and SIGNAL_OFF, as shown in Figure 1.
ELECTRICAL CHARACTERISTICS (continued)
(V CC = +2.97V to +5.5V, PECL outputs are terminated with 50 Ω to V
CC - 2V, R TH = 100 Ω, C
AZ = 0.1µF, C SD = 1nF, T A = -40°C to
+85°C. Typical values are at V CC = +3.3V, T A = +25°C, unless otherwise noted.)
PARAMETER SYM B O L CONDITIONS MIN TYP MAX UNITS
TRANSFER CHARACTERISTICS
Bandwidth Gain = 60dB 150 250 MHz
C AZ = open 500
Low-Frequency Cutoff
C AZ = 0.1µF 0.5
kHz
LOSS-OF-SIGNAL SPECIFICATIONS (Notes 2, 4, 6)
LOS Sensitivity Range 0 Ω ≤ R
TH
≤ 2kΩ 2 20 mV P-P
LOS Hysteresis 10log (V DEASSERT /V ASSERT ) 1.4 2 dB
LOS Assert/Deassert Time (Note 7) 2.3 80.0 µs
R TH = 0 Ω, low setting 0.5 0.9 1.3
R TH = 1k Ω, medium setting 4.8 6.6 8.3 LOS Assert Level
R TH = 2k Ω, high setting 12 17 22
mV P-P
R
TH
= 0 Ω, low setting 1.1 1.5 1.9
R TH = 1k Ω, medium setting 8.0 10.8 13.5 LOS Deassert Level
R TH = 2k Ω, high setting 20 28 36
mV P-P
Signal-Dectect Filter Resistance R SD Pin 7 14 20 26 k Ω
Figure 1. Signal Levels for LOS Assert/Deassert Time
Measurement
TIME
V IN
MAXIMUM DEASSERT LEVEL
1dB
6dB MAXIMUM POWER-DETECT WINDOW
SIGNAL ON
SIGNAL OFF
MINIMUM ASSERT LEVEL
0V