Low the pulse oxy meter which possesses the light-emitting diode drive of electric power consumption type

摘要

A photometer (10) includes a light source (12) operable to direct light toward a sample (14), a detection circuit (16) operable to detect the light after it has passed through the sample, and a drive circuit (18) for powering the light source. The drive circuit includes an input (20) for coupling with a source of power and energy storage circuitry (22) coupled with the input. The energy storage circuitry is operable to store energy from the source of power when switched to a charging state and to deliver current to the light source in a ramped manner when switched to a discharge state so that the current peaks at a selected time. The drive circuit delivers a controlled amount of current to the light source that peaks only after the detection circuit has settled so that power is not wasted at the startup of the oximeter.