On Wed, 17 Feb 2010 15:43:53 -0200, "Lucas Tanure" said: > wow too expensive!! I'd say "a little too expensive". The L6203 from ST is slightly less expensive but comparable. The main problem is when a chipmaker gets into parts that can handle 100 watt loads, they tend to add a feature here or there so it will sell into a few different applications, and the price goes up. Small H-bridges are used everywhere, so they are plentiful and can be more specialized, and cost a dollar. If you design an h-bridge to meet your voltage, current, and frequency needs with or without protection, then you can get the parts cost down. But you will have had to design it and also fit it into your board. If your current is low, bipolar h-bridges make sense and everything is simple and inexpensive. Over a few amps, you start thinking MOSFETs. If your motor voltage is 10-15 volts then it is real easy to design a MOSFET h-bridge. If you want something that handles a broad voltage range, it instantly gets twice as complicated. A lot of "ifs" :) What's your voltage? Cheerful regards, Bob -- http://www.fastmail.fm - IMAP accessible web-mail -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist