Analog Integrated Circuit Device Data

Freescale Semiconductor

17

34830

TYPICAL APPLICATIONS

PCB LAYOUT CONSIDERATIONS

The 34830 is a high-speed amplifier, and as such requires

careful attention to be paid to the way in which boards are laid

out, in order to guarantee best performance. All high-speed

layout techniques should be followed including the following

points.

1. Minimize all trace inductances by reducing trace

lengths. This is especially critical for the supply and

ground lines as well as for the output line. Boards with

multiple layers should have enough vias from the

ground plane to the chip ground connection to further

reduce inductance.

2. Make sure that a solid ground plane is available and

run all traces above it.

3. Avoid traces with 90 degree bends.

4. Use a 0.1μF bypass capacitor in series with a 4.7

Ω

as possible. Include a 10μF bypass capacitor at the

connected to the external world.

5. Try to refer all ground connections to the same point as

in a star ground configuration. Usually this point is the

middle point of the ground plane.

THERMAL CONSIDERATIONS

Make sure that the thermal dissipation ratings for the

34830 package are not violated in the application at hand.

The 34830 comes in a package with an exposed pad (EP).

The primary function of the EP is to serve as an effective way

to dissipate heat away from the inside of the package. Take

full advantage of this feature and connect the EP to a surface

or plane that can act as a heat sink. The EP is electrically

connected to ground. Make sure that the heat sink is also

connected to the same potential. If multiple heat generating

components are used in the application, distribute these

evenly throughout the board, so as not to create hot spots

with large temperature gradients that could violate power and

heat dissipation ratings.

POWER DISSIPATION

Care must be taken not to exceed the maximum die

junction temperature of the 34830. The die junction

temperature can be calculated through the formula:

EN

1

E-Switch

Switch SPDT

SPDT, EG1218

Y

VCC

1

2POL254 Phoenix

Connector

Termblock2_MKD

MKDSN1.5/2, 2 pin Terminal block 2 Diga-

key, 5.0mm, 90 deg wire to pin, Stock

number - 277-1236-ND

Y

Freescale does not assume liability, endorse, or warrant components from external manufacturers that are referenced in circuit drawings or

tables. While Freescale offers component recommendations in this configuration, it is the customer’s responsibility to validate their application.

Table 5. 34830 Bill of Material

Item

Qty

Part Description

Value/Rating

Part Number/Manufacturer

Install

×

+

=