EL5171 INTERSIL [Intersil Corporation], EL5171 Datasheet - Page 12

• Manufacturer Part Number: EL5171
• Description: 250MHz Differential Twisted-Pair Drivers
• Manufacturer: INTERSIL [Intersil Corporation]

• ΔV
• R
• I
• i = Number of channels
By setting the two PD
can solve the output current and R
overheat.
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high frequency device, a good printed circuit
board layout is necessary for optimum performance. Lead
lengths should be as sort as possible. The power supply pin
must be well bypassed to reduce the risk of oscillation. For
normal single supply operation, where the V
connected to the ground plane, a single 4.7µF tantalum
capacitor in parallel with a 0.1µF ceramic capacitor from V
Typical Applications
application
LOAD
LD
O
DC Gain
(
R
75
HF
= Differential load resistance
= Maximum differential output voltage of the
T
= Load current
)Gain
R
R
GC
C
T
L
=
=
1
1
R
+
R
G
+
G
2R
---------- -
MAX
R
--------------------------
R
G
G
F
2R
||
equations equal to each other, we
R
F
GC
12
FBP
IN+
IN-
REF
FBN
FBP
I
I
REF
FBN
N
N
LD
+
-
R
R
EL5171/
EL5371
to avoid the device
R
R
F
F
F
F
FIGURE 27. TWISTED PAIR CABLE RECEIVER
S
- pin is
FIGURE 28. TRANSMIT EQUALIZER
EL5171, EL5371
50
50
V
V
S
O
O
+
-
+
TWISTED PAIR
Z
O
= 100Ω
to GND will suffice. This same capacitor combination should
be placed at each supply pin to ground if split supplies are to
be used. In this case, the V
supply rail.
For good AC performance, parasitic capacitance should be
kept to a minimum. Use of wire wound resistors should be
avoided because of their additional series inductance. Use
of sockets should also be avoided, if possible. Sockets add
parasitic inductance and capacitance that can result in
compromised performance. Minimizing parasitic capacitance
at the amplifier's inverting input pin is very important. The
feedback resistor should be placed very close to the
inverting input pin. Strip line design techniques are
recommended for the signal traces.
As the signal is transmitted through a cable, the high frequency
signal will be attenuated. One way to compensate this loss is to
boost the high frequency gain at the receiver side.
R
GAIN
(dB)
GR
f
f
L
H
≅
≅
------------------------ -
2πR
---------------------------- -
2πR
1
IN+
IN-
REF
G
GC
1
f
C
L
C
C
EL5172/
C
EL5372
R
S
FR
- pin becomes the negative
f
H
V
FREQUENCY
O
August 10, 2010
FN7307.7