EL1519
Typical Performance Curves
1.4
POWER DISSIPATION (W)
R
F
=500Ω
1.2
1
0.8
0.6
0.4
0.2
0
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
781mW
θ
J
SO
60
8
A
=1
JEDEC JESD51-3 LOW EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
A
V
=5
V
S
=±6V
R
L
=100Ω
R
F
=750Ω
R
F
=1kΩ
°C
/W
100K
1M
(Hz)
10M
100M
FIGURE 25. DIFFERENTIAL FREQUENCY RESPONSE vs R
F
FIGURE 26. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
JEDEC JESD51-7 HIGH EFFECTIVE THERMAL
CONDUCTIVITY (4-LAYER) TEST BOARD
3.5
POWER DISSIPATION (W)
3
2.5
2
1.5
1
0.5
0
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
1.136W
SO8
110°
C /W
FIGURE 27. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
Applications Information
Product Description
The EL1519 is a dual operational amplifier designed for
customer premise line driving in DMT ADSL solutions. It is a
dual current mode feedback amplifier with low distortion
while drawing moderately low supply current. It is built using
Elantec's proprietary complimentary bipolar process and is
offered in industry standard pin-outs. Due to the current
feedback architecture, the EL1519 closed-loop 3dB
bandwidth is dependent on the value of the feedback
resistor. First the desired bandwidth is selected by choosing
the feedback resistor, R
F
, and then the gain is set by picking
the gain resistor, R
G
. The curves at the beginning of the
Typical Performance Curves section show the effect of
varying both R
F
and R
G
. The 3dB bandwidth is somewhat
dependent on the power supply voltage.
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high frequency device, good printed circuit
board layout is necessary for optimum performance. Ground
plane construction is highly recommended. Lead lengths
should be as short as possible, below 1/4”. The power
supply pins must be well bypassed to reduce the risk of
oscillation. A 1.0µF tantalum capacitor in parallel with a
0.01µF ceramic capacitor is adequate for each supply pin.
For good AC performance, parasitic capacitances should be
kept to a minimum, especially at the inverting input. This
implies keeping the ground plane away from this pin. Carbon
resistors are acceptable, while use of wire-wound resistors
should not be used because of their parasitic inductance.
Similarly, capacitors should be low inductance for best
performance.
7
FN7017.2
April 10, 2007