Datasheet

Evaluation Schematics

1-2

1.1 Evaluation Schematics

As delivered, the EVM has a fully functional example circuit; just add power

supplies, a signal source, and monitoring instrument. See Figure 1−1 and

Figure 1−2 for the default schematic diagrams. The user can change the gain

by changing the ratios of the feedback and gain resistors (see the device data

sheet for recommended resistor values). The EVM includes the following

features:

J Wide operating supply voltage range: single supply 3 Vdc to dual sup-

ply ±7.5 Vdc operation (see the device data sheet). Single supply op-

eration is obtained by connecting both GND and −VS to ground.

J Convenient GND test point (TP1).

J Power supply ripple rejection provided by inductors FB1 and FB2 fol-

lowed by 22 µF capacitors.

J Decoupling capacitors on +VS and −VS populated with 0.1 µF and

100 pF.

J Nominal 50-Ω input impedance for the IN− inputs. Termination can be

configured according to the application requirement.

J A good example of high-speed amplifier PCB design and layout. Also

see High-Speed Amplifier PCB Layout Tips (SLOA102).

J 953-Ω resistors along with 50-Ω internal test equipment impedance

provides minimum load of 1 kΩ.

J User customizable/configurable component choice.

J Nominal 50-Ω signal traces for input and outputs to reduce reduce sig-

nal reflections wiithin this board.

J PowerPAD heatsinking capability

The default configuration for the EVM is designed to provide a 50-Ω terminated

voltage gain of −1 with the amplifier loaded with approximately 1 kΩ. This

voltage gain is the ratio of the voltage at the output pin of the amplifier (pin 1)

to the voltage at the input at J1. The EVM also provides a nonterminated gain

of 1.96 from the noninverting input connector J2 to the output pin of the

amplifier (pin 1).