7

Applications Information

Product Description

The EL5106 and EL5306 are fixed gain amplifier that offers

a wide -3dB bandwidth of 350MHz and a low supply current

of 1.5mA. They work with supply voltages ranging from a

single 5V to 12V and they are also capable of swinging to

within 1.2V of either supply on the output. These

combinations of high bandwidth and low power make the

EL5106 and EL5306 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

EL5191 with 1GHz on a 9mA supply current or the EL5162

with 300MHz on a 4mA supply current. Versions include

single, dual, and triple amp packages with 5-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.

Disable/Power-Down

The EL5106 and EL5306 amplifiers can be disabled placing

their output in a high impedance state. When disabled, the

amplifier supply current is reduced to <25µA. The EL5106

and EL5306 are disabled when its CE pin is pulled up to

within 1V of the positive supply. Similarly, the amplifier is

enabled by floating or pulling the 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 EL5106

and EL5306 to be enabled by tying CE to ground, even in 5V

single supply applications. The CE pin can be driven from

CMOS outputs.

Gain Setting

The EL5106 and EL5306 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 13

shows the amplifier in gain of +2 configuration. The gain

error is ±2% maximum. Figure 14 shows the amplifier in gain

of -1 configuration. For gain of +1, IN+ and IN- should be

connected together as shown in Figure 15. 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 13. PACKAGE POWER DISSIPATION vs AMBIENT TEMPERATURE

AMBIENT TEMPERATURE (°C)

0

0.4

1.4

1.2

1

0.8

0.6

0.2

0

25

50

75

100

150

125

85

JEDEC JESD51-7 HIGH EFFECTIVE THERMAL

CONDUCTIVITY TEST BOARD

0.1

1.250W

QSOP16

909mW

893mW

435mW

SO8

SOT23-6

SO16 (0.150”)

-

+

325

Ω

325

Ω

IN-

IN+

EL5106, EL5306