SU920821A1 - Device for control of electroluminiscent indicator - Google Patents

Description

(St) DEVICE FOR CONTROLLING ELECTROLUMINESCENT

INDICATOR

I

The invention relates to automation and computing technology and is intended to display alphanumeric information on electroluminescent indicators, ELI and screens.

There are known devices for controlling an electroluminescent indicator, comprising transistor switches, resistors, diodes, an electroluminescent capacitor connected to collectors of transistor switches, a control bus and a clock bus, inverse pulses 1.

The disadvantage of such devices is that with the alternate opening of transistor switches for the duration of the clocking inverse pulses, the power consumed from the power source is used up on their collector resistances.

Closest to the invention to the technical nature of the device is to control the ELI, containing

, sting transistor switches, ELC connected to collectors of transistor switches, elements NOT and AND-OR-NOT, informational inputs of which are connected to clock buses of inverse pulses, and their control inputs directly and through the element NOT to control bus, and one of transistor switches connected to one bus clock pulses, and the input of the other - with the output element AND-OR-NOT 2.

However, by alternately opening the transistor switches for the duration of the clocking inverse pulses, the power consumed from the power source is used up on their collector resistances. The desire to reduce power consumption by increasing the collector resistance of the effect is prevented, on the one hand, by reducing the voltage on a closed transistor for estimating an increase in the voltage drop by 39 this resistance as the reverse collector current flows through it 3. which leads to a reduced voltage drop across the collector of the transistor switch, thereby causing a decrease in the luminance of the indicator, and, on the other hand, a decrease in the indicator recharge current, which also causes a decrease in the luminance of its luminescence. The purpose of the invention is to reduce the power required by the device. To achieve this goal, the control device in the electroluminescent indicator contains transistor switches, the collectors of which are connected to the plates of the electroluminescent indicator, the base with the same terminals oi of the limiting elements, and the emitters with the bus of zero potential, unevenness element connected with other conclusions of the first restrictive elements, other conclusions of the second restrictive elements are connected to the same power bus, the third and fourth restrictive elements are entered, and two Modes key transistor whose collector is connected to one terminal of the third restrictive elements and another supply bus, with one emitter terminal of the fourth restriction members and the electrodes of the electroluminescent indicator, and base - to other ends of the third and fourth restriction members. The drawing shows the principle on the device diagram. The device for controlling the ELI contains transistor switches 1 and 2 electroluminescent indicator (EL 3 connected to the collectors of transistor switches 1 and 2, the logical element k UNEMATICAL, two additional transistor switches 5 and 6, the first restrictive elements 7 and 8, the second restrictive elements. 9 and 10, the third limiting elements 11 and 12, the fourth limiting elements 13 and 1, the clock bus 15 and the control bus 16. The device works as follows. If there is a logical unit on the control bus, the image 16 by output of the logic element 4 UNEMNATABILITY there are impulses, antiphase impulses on the bus clock pulses 15-, such phasing of impulses leads to antiphase operation of transistor switches I and 2. At the same time, if transistor switch 1 (2) is open, then transistor. 5 (6) is closed due to the appropriate choice of the values of the resistive divider formed by the third and fourth limiting elements II and 12 (13 and I) (the values of resistors 11 and 12 are much larger than resistors 13 and 14). When transistor switch 1 (2) is closed, transis The orient switch 5 (6) is open and saturated, whereby the voltage on the collector of transistor switch 1 (2) is equal to the voltage of the power source E. Thus, the voltages on the collectors of transistor switches 1 and 2 change from zero to in antiphase, which means that ELI 3 has two-pole voltage pulses, the amplitudes of which are different-polarity equal to the voltage of the power source E ,, and are sufficient for normal luminescence of ELI 3. If there is a logical zero on the control bus of the image 16, the switching transistors are Items 1 and 2 will be in phase, which will lead to the absence of voltage pulses on ELI 3, causing it to go out completely. . The reduction in power consumption is due to the fact that the values of resistors 11 and 12 are chosen several tens of times (on the order of 10-30) greater than the values of the collector resistances of the transistor keys in the known device. Therefore, when the transistor switches 1 or 2 are open, there is a much lower current consumption, and therefore power, from the power source E. Increasing the values of resistors, limiting elements 11 and 12 on the one hand does not lead to an increase in the constant recharge time of ELI 3, and thus to a decrease in the luminance of its luminescence, since the time constant is determined not by the values of these resistors, but by small values of the output. resistances of both saturated transistor switches 5 and 6, and open transistor switches 1 and 2, and the other side does not reduce the voltage drop across the collectors of transistor switches 1 and 2, since this prevents saturation by an additional 5 tons 5 and 6 transistor switches, so that the voltage drop is maximum and equal to the value of the power supply voltage E.10

A significant reduction in the power consumed by a device leads to the fact that the power loss, defined as the sum of the power over the device control circuit (the logic element UNABILITY, the control and displacement circuits of the transistor switches) and the power caused by the flow of direct current in the resistive elements of the device at 20 the opening of the transistor switches is reduced to almost the level of useful power consumed by the ELC. This ratio of useful power and power loss gives a noticeable positive effect when using the proposed device, especially in electroluminescent screens, where the number of ELI is quite significant.

Claims (2)

JQ claims A device for controlling an EL indicator containing transistor switches, the collectors of which are connected to the plates of the electroluminescent indicator, the base with one of the limiting elements, and the emitters with the zero potential bus, unequal element connected with the other conclusions of the first restrictive elements Connected to a single power bus, characterized in that, in order to reduce power consumption, third and fourth The limiting elements and two additional transistor switches, the collectors of which are connected to one of the outputs of the third restrictive elements and another power bus, the emitters - with one from the fourth limiting elements and the plates of the electroluminescent indicator, and the base from the other to the third and fourth restrictive elements. Sources of information taken into account in the examination one . Copyright certificate. USSR № 363089. class. G 06 F 3/1, 1973. 2. USSR author's certificate ff 723618, cl. G 06 K 15/18, 1978 (prototype).