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M02050 Datasheet, PDF (1/2 Pages) M/A-COM Technology Solutions, Inc. – Limiting Amplifier for Applications up to 2.5 Gbps
Limiting Amplifier for Applications up to 2.5 Gbps
M02050
M02050 can support either a 3.3V or 3.3V/5V supply > K E Y F E A T U R E S
The M02050 is an integrated high-gain limiting amplifier.
Featuring PECL outputs, the M02050 is usable in applica-
tions up to 2.5 Gbps. Full output swing is achieved even at
minimum input sensitivity. The M02050 operates with a 3.3V
or 3.3V/5V supply.
> 4 mV maximum input sensi-
tivity at 2.5 Gbps
> PECL outputs
> Rate selection for ≤ 1.25
Gbps
> Average and peak-to-peak
receive power monitor
outputs
> Low power (< 180 mW)
> 16 pin 3x3 QFN,
standard/green package
Rate select is supported for SFP applications and/or to
achieve optimum sensitivity at data rates ≤ 1.25 Gbps. When
rate select is high, optimum sensitivity is achieved at 2.5
Gbps.
The M02050 also includes two analog RSSI outputs propor-
tional to either the average or peak-to-peak input signal and
a programmable signal-level detector allowing the user to
set thresholds at which the logic outputs are enabled. The
M02050 is pin compatible with the M02040 2.1 Gbps post
amplifier.
Inputs
The data inputs are internally connected to VTT via 50Ω
resistors, and generally need to be AC coupled. The nominal
VTT voltage is 2.85V because of the internal resistor divider
to VCC, which means this is the DC potential on the data
inputs. See the applications information section for further
details on choosing the AC-coupling capacitor.
DC Offset Compensation
M02050 contains an internal DC autozero circuit that can
remove the effect of DC offsets without using external
components. This circuit is configured such that the feed-
back is effective only at frequencies well below the lowest
frequency of interest. The low frequency cut off is typically
25 kHz.
PECL Outputs
The M02050 features 100k/300k PECL compliant outputs.
The outputs may be terminated using any standard AC or
DC-coupling PECL termination technique. AC-coupling is
used in applications where the average DC content of the
data is zero e.g. SONET. The advantage of this approach is
lower power consumption, no susceptibility to DC drive and
compatibility with non-PECL interfaces.
Loss of Signal (LOS)
The M02050 features input signal level detection over an
extended range. Using an external resistor, RST, between pin
STSET and VCC, the user can program the input signal
threshold. The LOS signal is active when the signal is below
the threshold value. The signal detection circuitry has the
equivalent of 3.5 dB (typical) electrical hysteresis. RST
establishes a threshold voltage at the STSET pin. Internally,
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