Below is a scope shot of the ST1 and ST2 pins of the MAX13256 in a typical configuration with a 50mA load using the internal oscillator. At room temperature, this duty cycle varies by about 0.006%.
Below is a scope shot of the ST1 (channel 1) and ST2 (channel 2) pins of the MAX13256 in a typical configuration with a 350mA load using an external clock (channel 3). At room temperature, the duty cycle of the ST1 and ST2 driver outputs vary by about 0.007% maximum.