Help with an h bridge controller

  • Thread starter Thread starter rockstar
  • Start date Start date
  • Tags Tags
    Bridge Controller
AI Thread Summary
The discussion focuses on using p-type MOSFETs for an R/C car's H-bridge controller, specifically questioning the feasibility of avoiding voltage pump circuits while still enabling PWM torque control. The user has replaced n-type MOSFETs with p-types due to lower internal resistance, which is crucial for handling high current in a large 1:4 scale R/C car. There is a debate about the performance of n-channel versus p-channel MOSFETs, with some participants suggesting that n-channel devices may offer better performance. The conversation includes requests for datasheets of the specific MOSFETs being used to assess their suitability. Overall, the thread emphasizes the challenges of optimizing MOSFET selection for efficient control in high-current applications.
rockstar
Messages
8
Reaction score
0
i'm using p type mosfets for an r/c cars h bridge controller (the two n types have been replaced with p types because of their lower internal resistance) and was wondering if there is a way to do it without voltage pump circuits that stills alllows a P.W.M. torque controller.
 
Engineering news on Phys.org
So you're using p-type mosfets for the low-side switches as well?

EDIT -- I would have thought the n-fets would have better performance. What are the devices?
 
berkeman said:
So you're using p-type mosfets for the low-side switches as well?

EDIT -- I would have thought the n-fets would have better performance. What are the devices?

large 1:4 scale r/c car and use a LOT of current the difference in the internal resistance was becoming a problem in heating, and srry it was n types just i was typeing without thinking
 
Last edited:
Okay, so you want to use n-channel power MOSFETs for the high-side switches instead of p-channel. Hmmm, got to think about that one. Do you have a pointer to the n-channel device datasheets? And maybe one to the p-channel FETs that you are trying to replace.
 
Very basic question. Consider a 3-terminal device with terminals say A,B,C. Kirchhoff Current Law (KCL) and Kirchhoff Voltage Law (KVL) establish two relationships between the 3 currents entering the terminals and the 3 terminal's voltage pairs respectively. So we have 2 equations in 6 unknowns. To proceed further we need two more (independent) equations in order to solve the circuit the 3-terminal device is connected to (basically one treats such a device as an unbalanced two-port...
suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts with terminal 1 being - (negative) and terminal 2 being + (positive). you connect the voltmeter to terminal A2 and to terminal B1. does it read any voltage? can - of one capacitor discharge + of the...
Back
Top