Using binary coded decimal BCD , we can display any numerical digit on the 7 segment display from 0 to 9- using only 4 pins. Lastly, the 8 output pins are labeled a, b, c, d, e, f g, which are pins 12, 12, 11, 10, 9, 15, and Note in the cases of Figures 6 and 7 that an NPN buffer transistor must be interposed between each output drive segment and the input segment of the display. The combination of pushbuttons pressed and unpressed determines the decimal digits, according to the binary value. A BCD to 7 segment decoder circuit is a circuit that intakes a binary value and displays the equivalent decimal value on the 7 segment display.

Uploader: Kikora
Date Added: 21 December 2013
File Size: 32.24 Mb
Operating Systems: Windows NT/2000/XP/2003/2003/7/8/10 MacOS 10/X
Downloads: 58248
Price: Free* [*Free Regsitration Required]

How to Build a 4511 BCD to 7 Segment Decoder Circuit

The chip takes in a binary value and displays the equivalent decimal value on the 7 segment display. Below, we will also explain how BCD to 7 segment display decoders work in great detail, specifically the chip.

We can choose what digit we want to display by inputting the equivalent binary value into these data pins. So we can see which combinations of pushbuttons turned on displays which decimal values.

Using Seven-Segment Displays — Part 2

Figures 6, 7and 8 show how to modify the above circuit to drive LED common-anode displays, gas discharge displays, and low-brightness fluorescent displays, respectively. Finally, the LE latch enable terminal pin 5 enables the IC to give either direct or latched decoding operation.


Figure 5 shows the basic connections for driving a common-cathode LED display. Any value above this 74hc45111 cannot be shown on the 7 segment LED display.

When unpressed, the pin will be HIGH. Functional diagram and pin notations of the B decade counter with seven-segment display driver.

Way of using the B to drive a seven-segment LCD. Driving a gas discharge readout with a B. The B has four input control 74yc4511, and three auxiliary output terminals.

How to Build a BCD to 7 Segment Decoder Circuit

This pin is active LOW. Series Using 7-Segment Displays All articles in this series: Driving a fluorescent readout with a B.

So the 7 segment LED display will show a 0 initially. These data pins are referred to in the datasheet as D, B, C, and A. If 74h4c511 B ICs are required to give automatic leading-zero suppression, the basic Figure 17 circuit must be modified as shown in Figure 18 774hc4511 provide ripple-blanking operation. We cannot show any other digits on the 7 segment display. The LT terminal drives all display outputs on when the terminal is driven to logic 0 with the RBO terminal open or at logic 1.

With the binary value input, the equivalent decimal value of that binary number is displayed on the 7 segment display. When HIGH, the lamp test is activated. Pin 4 is the Blanking pin. In each case, Rx determines the operating segment current 74nc4511 the display, and Ry determines the base current of the transistor.


This feature enables the IC to act as a universal unit that can drive common-cathode or common-anode LED eisplay liquid-crystal seven-segment displays with equal ease, as shown in Figures 10 to The rest of this article describes a few of the most popular of these devices.

Arduino + 7 Segmentos (74HC, 74HC) – Ricardo Sequeira

These 4 data pins are fed binary values. When the not-LATCH terminal is pulled low, the BCD input signals that are present at the moment of transition are 744hc4511 into memory and fed in decoded form to the seven-segment outputs until the not-LATCH 7h4c4511 returns to the high state. The not-BL pin 4 terminal is also normally displya high, but blanks turns off all seven segments when pulled low.

For example, a on the matches to a on the 7 segment LED display, b matches with b, etc. The decimal equivalent of the binary value that it holds will be displayed on the 7 segment display. It’s simply to test all the outputs to check if they turn on.

Basic way of using the B to drive a seven-segment common-cathode LED display. For example, if we want to display 6 on the 7 segment display, we input the value into the DBCA data pins.