Hello guys,
One of my customers is manufacturing some products which DDC112 is used for a photo diode (PD) current sensing.
In the manufacturing, they found that some of DDC112 (about 2%) output data showed higher current than others (about 98%) when PD is covered completely from light .
They thought the cause might be PD manufacture variation. So they removed PD. Then DDC112 IN1 was connected to only 22pF capacitor. The capacitor opposite
terminal is connected to GND. But same DDC112 showed higher current than others too at the conndition.
The followings are those DDC112 output.
DDC112 which outputs higher data (categolized in 2%)
output data standard deviation
1.81527pA 0.02865
1.81748pA 0.02850
1.81800pA 0.03045
DDC112 (others- categolized in 98%)
output data standard deviation
1.81410pA 0.02239
1.81337pA 0.02197
1.81312pA 0.02363
The followings are the result when capacitor connected to IN1 and GND was exchenged to exclude capacitor cause.
DDC112 which outputs higher data (categolized in 2%)
output data standard deviation
1.82209pA 0.02661
1.82182pA 0.02650
1.82303pA 0.02982
DDC112 (others- categolized in 98%)
output data standard deviation
1.81167pA 0.02182
1.81145pA 0.02315
1.81108pA 0.02344