From your email it appears that the regulation of your 12V output is poor and you would like to improve it.
In a multiple output flyback converter with only one output regulated using the feedback circuit, the additional outputs which are cross regulated, will suffer from voltage variation especially for a large change in load current. For such applications it is benificial to use a weighted feedback circuit. In a weighted feedback circuit, the output voltage is regulated by using a circuit that weighs the output voltage of multiple outputs. Although this results in slight degradation of the voltage regulation of the main regulated output, it helps to limit the variation of the additional outputs.
Please see AN-22 for reference (specifically page 12). Please use the link below to download AN-22.
Should you continue to experience a problem, please contact our office in India. Our Application engineering group in India will be able to help you resolve the issue.
contact information of our office in India is as follows:
# 1, 14th Main Road
Bangalore 560052 India