+5V

C4

C2

.01PF

6.8PF

.1PF

C1

C3

.01PF

6.8PF

C5

+

-

50:

50:

OUT

IN

300:

300:

-5V

LMH6714, LMH6720

LMH6722, LMH6722-Q1

SNOSA39G – NOVEMBER 2002 – REVISED APRIL 2013

www.ti.com

Disabled, the LMH6720 inputs and output become high impedances. While disabled the LMH6720 quiescent

current is approximately 500

The disable function can be used to create analog switches or multiplexers. Implement a single analog switch

with one LMH6720 positioned between an input and output. Create an analog multiplexer with several

shunt signals to ground.

DISABLE LIMITATIONS (LMH6720 ONLY)

the LMH6720 inputs and output become very high (>1M

effective output impedance.

diodes will also conduct if the signal leakage through the feedback resistors brings the inverting input near either

supply rail.

Figure 35. Typical Application with Suggested Supply Bypassing

LAYOUT CONSIDERATIONS

Whenever questions about layout arise, use the evaluation board as a guide. The following Evaluation boards

are available with sample parts:

LMH6714

SOT-23

LMH730216

SOIC

LMH730227

LMH6720

SOT-23

LMH730216

SOIC

LMH730227

LMH6722

SOIC

LMH730231

TSSOP

LMH730131

To reduce parasitic capacitances, the ground plane should be removed near the input and output pins. To

reduce series inductance, trace lengths of components in the feedback loop should be minimized. For long signal

paths controlled impedance lines should be used, along with impedance matching at both ends.

Bypass capacitors should be placed as close to the device as possible. Bypass capacitors from each rail to

ground are applied in pairs. The larger electrolytic bypass capacitors can be located anywhere on the board, the

smaller ceramic capacitors should be placed as close to the device as possible. In addition Figure 35 shows a

capacitor (C1) across the supplies with no connection to ground. This capacitor is optional, however it is required

for best 2nd Harmonic suppression. If this capacitor is omitted C2 and C3 should be increased to .1

μF each.

12

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Product Folder Links: LMH6714 LMH6720 LMH6722 LMH6722-Q1