OB1203 Certification Preparation, Setup, and Test Procedure
X0119984 Rev.1.0
Mar 11, 2021
Page 11
If the DUT screen stays in “Adjust to 50” (50 is the normalized ADC count for both, red, and IR in test mode),
the WhaleTeq LED(s) is producing too much light output for the DUT to reach its nominal operating range.
In this case, reduce the IR DC and Red DC values in the WhaleTeq GUI until the DUT leaves the “Adjust to
50” screen. Then adjust the IR and Red DC values so that the DUT Display reads 60.000 for IR and 40.000
for Red.
Table 2. Test Results and Calculation of Fixture Factor
Color
Standard
ADC Counts
Fixture Factor FF = Standard / Measured
IR
60.000
<calculate FFIR>
FFIR =
IR DC Level [mV] / 1000 mV
Red
40.000
<calculate FFRed>
FFRed =
Red DC Level [mV] / 2000 mV
Note
: The FFIR and FFRed fixture factors should be applied to all of the AECG100 Red and IR settings
moving forward in the procedure.
3. Proceed to next step.
6. DUT Determination and Correction of Sp02 Errors Induced by
External Optical Crosstalk
6.1
Background
The OB1203 is designed to be used either in direct contact with skin or with a secondary cover window.
If the final DUT implementation uses an additional cover window, it may provide a path for additional optical
crosstalk between the LEDs and the detector. Because this cross-coupled light can induce Sp02 measurement
errors, Renesas recommends that it to be determined and compensated for. The following procedure describes
how to determine the amount of crosstalk and how it can be eliminated at the DUT system level.
6.2
Methods
1. Simulator testing is used to predict the impact of a secondary cover window on the Sp02 performance of the
DUT.
2. A software correction factor is developed to compensate for crosstalk effects of the cover window.
3. The effectiveness of the correction factor is verified on the simulator.
The following figure shows the various light paths possible between the emitters and detector on a typical
reflectance oximeter.
