Modulele care combină cele trei culori sunt folosite în ecrane video mari și în programe reglabile de culoare (folosind asazisele led-uri RGB).Primele LED-uri albastre au fost produse în 1971 folosind nitrură de galiu de către Jacques Pankove de la RCA Laboratories. When higher output drive currents are required for single-ended operation, Ql and Q2 may be connected in parallel, and the output mode control pin must be tied to ground to disable the flip-flop. The circuit shown in Figure 14-14 may be used with almost any type of regulator circuitry; however, the circuit shown in Figure 14-15 should only be used in linear type supplies where the filter capacitor is isolated from the line. The use of circuits such as these will allow such systems to «die with dignity.» The circuits shown in Figures 14-14 and 14-15 both perform essentially the same function. The line voltage tolerance for proper operation is — 10, +20% of nominal.
Operation of the boost circuit (Figure 10-2B) is more subtle in that it first stores energy in a choke and then delivers this plus energy from the input line to the load. Full-Wave or Full-Wave Center Tap 1 » Full-Wave Bridge Figure 8-1. Rectification Schemes 8-1 In this section, specification of the filter capacitor, rectifier and transformer ratings will be discussed. When you need it, it’s always ready to use.
The whole ‘main’ consists just out of a select / case structure. The Zener Diode Reference The simplest form of a voltage reference is shown in Figure l-3a. It consists of a resistor and a zener diode. Pin Numbers in Parenthesis are for the Dual In-Line Package. Spre exemplu, dacă limita superioară de tensiune a unui driver de LED-uri este 28V iar VF = 2V, pe un singur sir putem conecta cel mult 14 LED-uri.