EL5308 Intersil Corporation, EL5308 Datasheet - Page 8

• Manufacturer Part Number: EL5308
• Description: Triple, 450MHz, Fixed Gain Amplifier With Enable
• Manufacturer: Intersil Corporation

Typical Performance Curves
Applications Information
Product Description
The EL5108 and EL5308 are fixed gain amplifiers that offer a
wide -3dB bandwidth of 450MHz and a low supply current of
3.5mA per amplifier. They work with supply voltages ranging
from a single 5V to 10V and they are also capable of
swinging to within 1.2V of either supply on the output. These
combinations of high bandwidth, low power, and high slew
rate make the EL5108 and EL5308 the ideal choice for many
low-power/high-bandwidth applications such as portable,
handheld, or battery-powered equipment.
For varying bandwidth and higher gains, consider the
EL5166 with 1GHz on a 9mA supply current or the EL5164
with 600MHz on a 3.5mA supply current. Versions include
single, dual, and triple amp packages with 6-pin SOT-23,
16-pin QSOP, and 8-pin or 16-pin SO outlines.
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high frequency device, good printed circuit board
layout is necessary for optimum performance. Low
impedance ground plane construction is essential. Surface
mount components are recommended, but if leaded
components are used, lead lengths should be as short as
possible. The power supply pins must be well bypassed to
reduce the risk of oscillation. The combination of a 4.7µF
tantalum capacitor in parallel with a 0.01µF capacitor has
been shown to work well when placed at each supply pin.
FIGURE 19. PACKAGE POWER DISSIPATION vs AMBIENT
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
1
0
0
JEDEC JESD51-3 LOW EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
909mW
625mW
633mW
391mW
TEMPERATURE
θ
25
JA
SOT23-6
AMBIENT TEMPERATURE (°C)
=256°C/W
SO16 (0.150”)
θ
JA
50
=110°C/W
8
75
85
θ
θ
100
JA
JA
QSOP16
=160°C/W
=158°C/W
SO8
(Continued)
125
150
EL5108, EL5308
Disable/Power-Down
The EL5108 and EL5308 amplifiers can be disabled and
placing their outputs in a high impedance state. When
disabled, the amplifier supply current is reduced to <25µA.
The EL5108 and EL5308 are disabled when the CE pin is
pulled up to within 1V of the positive supply. Similarly, the
amplifier is enabled by floating or pulling its CE pin to at least
3V below the positive supply. For ±5V supply, this means
that the amplifier will be enabled when CE is 2V or less, and
disabled when CE is above 4V. Although the logic levels are
not standard TTL, this choice of logic voltages allow the
EL5108 and EL5308 to be enabled by tying CE to ground,
even in 5V single supply applications. The CE pins can be
driven from CMOS outputs.
Gain Setting
The EL5108 and EL5308 are built with internal feedback and
gain resistors. The internal feedback resistors have equal
value; as a result, the amplifier can be configured into gain of
+1, -1, and +2 without any external resistors. Figure 21
shows the amplifier in gain of +2 configuration. The gain
error is ±2% maximum. Figure 22 shows the amplifier in gain
of -1 configuration. For gain of +1, IN+ and IN- should be
connected together as shown in Figure 23. This
configuration avoids the effects of any parasitic capacitance
on the IN- pin. Since the internal feedback and gain resistors
change with temperature and process, external resistor
should not be used to adjust the gain settings.
FIGURE 20. PACKAGE POWER DISSIPATION vs AMBIENT
1.4
1.2
0.8
0.6
0.4
0.2
0.1
1
0
0
JEDEC JESD51-7 HIGH EFFECTIVE THERMAL
CONDUCTIVITY TEST BOARD
1.250W
909mW
893mW
435mW
TEMPERATURE
θ
JA
SOT23-6
25
=230°C/W
IN-
AMBIENT TEMPERATURE (°C)
FIGURE 21. A
SO16 (0.150”)
50
θ
325Ω
IN+
JA
=80°C/W
75
85
V
325Ω
+
-
= +2
100
θ
θ
JA
JA
QSOP16
=110°C/W
=112°C/W
SO8
125
150