What this I²C accelerator does on the bus
The LTC1694IS5#TRM is a single-channel buffer and accelerator for 2-wire buses like I²C and SMBus. It sits between the master and the bus capacitance, actively driving the rising edge to meet the 400 kHz data rate without stretching the clock low time. Supply range of 2.7 V to 6 V covers both logic families, and the 60 µA quiescent current keeps the power budget tight in always-on bus segments.
Housed in a 5-lead TSOT-23-5 package (1.6 mm × 2.9 mm body), it fits tight PCB layouts where a larger SOIC-8 would crowd adjacent passives.