ADC driver in a 3x3 mm QFN — signal-chain fit
The Analog Devices LTC6400IUD-26#PBF is a fixed-gain differential ADC driver in the LTC6400 family, designed to interface directly between a high-speed analog source and a differential-input ADC. Listed for data-acquisition applications, this part handles the single-ended-to-differential conversion and common-mode level shifting that a modern pipeline or SAR ADC expects at its input. The 16-WFQFN footprint keeps the signal path short, which matters when driving sampling rates in the tens to hundreds of MHz range.
ROHS3 compliant, no exemption issues on the horizon. No need to qualify a substitute unless the design requires a different gain option.
Gain options in the same footprint
The LTC6400 family shares a common 16-QFN (3x3) pinout across gain variants. The -26 suffix denotes a specific fixed gain; siblings include the LTC6400IUD-20#PBF and LTC6400IUD-8#PBF, each with a different gain setting. All are in the same Tube package format and surface-mount package case. If the signal-chain gain budget changes, swapping to a different suffix within the LTC6400 family is a board-compatible change — same footprint, same supply rails, same application class.