Abstract—At present there are some power devices such as SCR Silicon Controlled Rectifier: Silicon Controlled Rectifier)in which it is necessary to pass a current through its gate so that it can control, for it is necessary to estimate a resistance (Rg)that gives the device to control the current needed, but which in turn that this current is so large that no damage to the rectifier, commonly this resistance (Rg) is the voltage control circuit, these circuits are used as AC to DC converters and other applications, however in practice the calculation of this resistance is not easy because the ground circuit control is floated; Another problem of resistances is very common for a TRIAC power device is of the family of transistors commonly connected to an optocoupler is, where the resistance is obtained from the optocoupler Rg may vary and should be considered in series. These resistors (Rg) are not calculated, we propose, in many cases the results obtained by the resistance proposals could damage the device or are not sufficient to control it with us into the loss of money and time. To solve the problem of resistance was created a digital prototype that calculates the optimum strength for this prototype device contains a power interface that allows you to enter the desired current value, the system varies its internal resistance in series with resistor arrays and measures the current value, giving us the optimum resistance value for the desired current, obtained as not to lose significant quantities of materials and time savings in design. In the results of the response of the electronic device designed, there was a percentage of error in the ohmic value of resistance and current measurement of ± 1%, which is very small, considering that this percentage is proportional to the error of each resistance involved and the type of resistance used .

Index Terms—Optimum current, power device, current, MOSFET, SCR, optimal resistance.

Ma. Del Rosario Osnaya, Leonardo Orozco, Miguel Rocha, César A.Calva, and Rafael Navarrete are with the Escuela Superior de Ingeniería Mecánica y Eléctrica, Instituto Politécnico Nacional, México (e-mail:chayo_fut1702@hotmail.com; mrocha@ipn.mx).
M. Isabel Rocha is with the Department of G. F. O., D-I. E, Universidad Politécnica de Valencia, España (e-mail: marocga@doctor.upv.es).
E. Andrade and C. Solis are with the Department of Physics, Universidad Nacional Autónoma de México.

Cite: M. R. Osnaya, M. F. Rocha, C. A. Calva, J. J. Bañales, L. Orozco, R. Navarrete, M. I. Rocha G., E.Andrade, and C. Solis, "Hardware to Determine the Optimal Value of Resistance by Current Measurements for TRIACs and SCRs Control," International Journal of Computer and Communication Engineering vol. 1, no. 4, pp. 309-312 , 2012.