M02050_17 Datasheet, PDF (16/28 Pages) M/A-COM Technology Solutions, Inc. – 3.3/5V Limiting Amplifier for Applications to 2.5 Gbps

Functional Description
3.3.6
JAM Function
When asserted, the active high power down (JAM) pin forces the outputs to a logic “one” state. This ensures that
no data is propagated through the system. The loss of signal detection circuit can be used to automatically force
the data outputs to a high state when the input signal falls below the threshold. The function is normally used to
allow data to propagate only when the signal is above the user's bit-error-rate requirement. It therefore inhibits the
data outputs toggling due to noise when there is no signal present (“squelch”).
In order to implement this function, LOS should be connected to the JAM pin shown in Figure 3-10, thus forcing the
data outputs to a logic “one” state when the signal falls below the threshold.
3.3.7
Rate Select Function
When the RATE_SEL pin (shown in Figure 3-10) is driven high, the M02050-15 bandwidth is set to its maximum
which allows the M02050-15 to operate at data rates up to 2.5 Gbps. When operating at data rates ≤ 1.25 Gbps,
then RATE_SEL should be tied low or left floating. This enables low-rate mode which reduces the bandwidth (and
thus the noise level) of the part.
Figure 3-10. JAM and RATE_SEL Input
V_CC
JAM or
RATE_SEL
R₁
R₂
R₁ = 55 kΩ for JAM, 30 kΩ for RATE_SEL
R₂ = 100 kΩ for JAM, 50 kΩ for RATE_SEL
02050-DSH-002-F
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