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LMH6554

SNOSB30O – OCTOBER 2008 – REVISED MARCH 2013

www.ti.com

When driven from a differential source, the LMH6554 provides low distortion, excellent balance, and common

observed in board layout. With an intrinsic device CMRR of greater than 70 dB, using 0.1% resistors will give a

worst case CMRR of around 50 dB for most circuits.

The circuit configuration shown in Figure 30 was used to measure differential S-parameters in a 100

Ω

environment at a gain of 1 V/V. Refer to Figure 28 in Typical Performance Characteristics VS = ±2.5V for

measurement results.

Figure 30. Differential S-Parameter Test Circuit

Single Ended Input To Differential Output Operation

In many applications, it is required to drive a differential input ADC from a single ended source. Traditionally,

transformers have been used to provide single to differential conversion, but these are inherently bandpass by

nature and cannot be used for DC coupled applications. The LMH6554 provides excellent performance as a

single-ended input to differential output converter down to DC. Figure 31 shows a typical application circuit where

an LMH6554 is used to produce a balanced differential output signal from a single ended source.

Figure 31. Single Ended Input with Differential Output

12

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