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Message ID: 245     Entry time: Tue Dec 15 13:38:34 2015
Author: Koji 
Type: Electronics 
Category: Characterization 
Subject: EOM Driver linearity check 

Linearity of the EOM driver was tested. This test has been done on Nov 10, 2015.

- Attachment 1: Output power vs requested power. The output start to deviate from the request above 22dBm request.

- Attachment 2: Ctrl and Bias voltages vs requested power. This bias was measured with the out-of-loop channel.
The variable attenuator has the voltage range of 0~15V for 50dB~2dB attenuation.

Therefore this means that:

- The power setting gives a voltage logarithmically increased as the requested power increases. And the two power detectors are watching similar voltages.

- And the servo is properly working. The control is with in the range.

- Even when the given RF power is low, the power detectors are reporting high value. Is there any mechanism to realize such a condition???

Attachment 1: Output_linearity.pdf  358 kB  Uploaded Tue Dec 15 17:12:31 2015  | Show | Hide all | Show all
Attachment 2: Ctrl_Bias.pdf  329 kB  Uploaded Tue Dec 15 17:12:47 2015  | Hide | Hide all | Show all
Ctrl_Bias.pdf
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