34063外加三極管

YDS512  INPUT 14-35V   OUT 12V  5A  
5.00元/只  (不隔離,共地)
YDS112      DC/DC (15-35V)/12V 1A                  1000PCS    3.00
YDS105      DC/DC (10-35V)5V 1A                    2000PCS    3.50
YDS212      DC/DC (15-35V)/12V 2A                  2000PCS    3.50
YDS205      DC/DC (15-35V) 5V 2A                   1000PCS    4.00
YDS224      DC/DC (26-40V) 24V 2A                   500PCS    4.00
YDSR3V3     DC/DC (7-35V) 3.3V 3A                  2000PCS    4.50
YDS305      DC/DC (7-35V) 5V 3A                    2000PCS    4.50
YDS312      DC/DC (15-35V)/12V 3A                  2000PCS    4.50
YDS512      DC/DC (15-35V)/12V 5A                  2000PCS    5.00
寧波市東林電子商行     鄔幼川
浙江省寧波市鄞奉路81號長城電子城C5--8
TEL: 0574-66852710 13777254660
FAX: 0574-87124300
Email:wuyouchuan007@163.com
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農(nóng)業(yè)銀行卡:9559980310166666811 戶名: 鄔幼川
交通銀行卡:60142820189715100   戶名: 鄔幼川

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用TL494

YDS512 是輸入15V-35V  輸出12V 5A 很簡單 (只要在輸入,輸出加兩只電解就OK了)
1127809926.txt

用BUCK,384*+MOS效率可以達(dá)到90%以上

請問那電路的短路好做嗎?