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How to choose the transistor and the current limiting resistor of the H-bridge?

I often see the H-bridge circuit for the 3V motor(Model: 130), VCC is 3V, the transistors are 8050 and 8550,

I have some 6V motors, can I lift the voltage of VCC to 5v and use this circuit to drive these motors?

Is this harmful to the 8050 and 8550?  

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sorry, I didn't remember it clearly. yes, the upper transistor should be 8550 PNP.



                                                                        ______|(VCC +3V)_____

                                                                        | E                              | E   

                                   _____R1 1K______B____Q1 8050                          Q2  8050_____B____R2 1K______  

                                  |                                      | C                            | C                                         |

    P2.7(AT89S52) _____|                                       | ____   MOTOR   __  |                                              |__P2.6(AT89S52)

                                  |                                      | C                             | C                                         |

                                  |_____R3 1K______B____Q3  8550                          Q4  8550_____B____R4 1K______|

                                                                        | E                                | E  



Logic limit : the P2.7 pin of the AT89S52 probably switches at a 5 volt level, so you should be able to switch both transistors if using a 5 volt supply. The 8550 PNP should be the upper transistor with the emitter tied to +5 volts, and its collector tied to the collector of the 8050 NPN, which also connects to a motor lead. The 8050 NPN should have it's emitter tied to ground. The 1k resistors are probably fine for protecting the AT89S522 pins. Note these transistors have no flyback diode prtection. For a low current motor, perhaps under 200 mA, they should be fine.
I click the Insert/edit image button ,but can not post a link to my schematic, oh my god!!
If you actually post a link to the circuit, perhaps more accurate help can be available.