I use LT6237 as a voltage follower in LTspice. Set input as a sine signal, middle value 1.8V , max 2.7V , min 0.9V ,10kHz. and supply voltage is 5V. Simulation result shows that when voltage is higher than about 1.3V, output match input, when voltage lower than 1.3V, output cannot match. The schematic and simulation as pictures. Is it normal ? waiting for reply!