el2142 Intersil Corporation, el2142 Datasheet - Page 4

• Manufacturer Part Number: el2142
• Description: Differential Line Receiver
• Manufacturer: Intersil Corporation

Applications Information
Gain Equation
V
GND
V
Choice of Feedback Resistor
For a gain of one, V
100Ω-200Ω improves the bandwidth. For gains greater than
Typical Applications Circuits
OUT
OUT
= ((R2+R1)/R1) x (V
= ((R2+R1)/R1) x (V
OUT
may be shorted back to V
IN
IN
-V
-V
4
INB
INB
+V
) when R1 tied to V
REF
FIGURE 2. COAXIAL CABLE DRIVER PAIR APPLICATION
FIGURE 1. TYPICAL TWISTED PAIR APPLICATION
) when R1 tied to
FB
, but
REF
EL2142
one, there is little to be gained from choosing resistor R1
value below 200Ω, for it would only result in increased power
dissipation and potential signal distortion. Above 200Ω, the
bandwidth response will develop some peaking (for a gain of
one), but substantially higher R1 values may be used for
higher voltage gains, such as up to 1kΩ at a gain of four
before peaking will develop.
Capacitance Considerations
As with many high bandwidth amplifiers, the EL2142 prefers
not to drive highly capacitive loads. It is best if the
capacitance on V
want gain peaking to develop. The V
potential pole in the feedback loop, so capacitance should be
minimized on this node for maximum bandwidth.
The amount of capacitance tolerated on any of these nodes
in an actual application will also be dependent on the gain
setting and the resistor values in the feedback network.
50Ω
50Ω
OUT
V
V
V
V
is kept below 10pF if the user does not
FB
IN
INB
REF
EL2142
100Ω
FB
node forms a
V
OUT
February 11, 2005
FN7049.1