74LS47, 74LS47 Datasheet, 74LS47 pdf, buy 74LS47, 74LS47 BCD to 7- Segment Decoder. 74LS47 component details, pinout & Datasheet. 74LS47 is a BCD to 7-segment decoder/driver IC & It accepts a binary coded decimal as input and converts it. Texas Instruments 74LS47 Encoders, Decoders, Multiplexers & Demultiplexers are available at Mouser Electronics. Mouser offers inventory, pricing.
|Published (Last):||19 July 2010|
|PDF File Size:||11.15 Mb|
|ePub File Size:||18.99 Mb|
|Price:||Free* [*Free Regsitration Required]|
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.
Way of using the B to drive a common-cathode or b common-anode seven-segment LED displays. They have integral ripple-blanking facilities, but do not incorporate data latches. Functional diagram and pin notations of the B decade counter with seven-segment display driver.
The segment output currents are internally limited to about 5mA at 10V or 10mA at 15V. Driving a low-brightness fluorescent readout.
If trailing-zero suppression is required, the direction of ripple-blanking feedback must be reversed with the RBI terminal of the LSD grounded and its RBO terminal wired to the RBI terminal of the next least-significant stage, and so on.
Figure 5 shows the basic connections for driving a common-cathode LED display.
The 74LS47 has active-low outputs designed for driving a common-anode LED display 74ls7 external current-limiting resistors Rxas shown in Figure 2. Figure 1 shows the functional diagrams and pin designations of these devices, each of which is housed in a pin DIL package. Figure 11 shows 74lls47 basic way of using the B 74lx47 drive a seven-segment LCD, and Figures 12 and 13 show it used to drive other types of seven-segment displays.
Driving a gas discharge readout with a B. The not-BL pin 4 terminal is also normally tied high, but blanks turns off all seven segments when pulled low. Driving a gas discharge readout. The IC does not incorporate a data latch and has no facility for ripple blanking.
Basic method of cascading B ICs without zero suppression.
The CO signal is a symmetrical square- wave at one-tenth of the CLK input frequency, and is useful in cascading B counters. If cascaded B ICs are required to give automatic leading-zero suppression, the basic Figure 17 circuit must 7l4s47 modified as shown in Figure 18 to provide ripple-blanking operation.
Series Using 7-Segment Displays All articles in this series: These multi-part series may be just what you need!
74LS47 IC | 74LS47 Datasheet | Pin Diagram & Description
Method of applying leading-zero suppression to the first three digits of a four-digit display using 74LS47 ICs. In Figure 12Rx sets the segment current of the display and Ry sets the base current of the transistor 10mA maximum.
The B can be used to drive most popular types of seven-segment displays. Finally, the LE latch enable terminal pin 5 enables the IC to give either direct or latched decoding operation. In each case, Rx determines the operating segment current of the display, and Ry determines the base current of the transistor.
Driving a fluorescent readout with a B.
74LS47 – BCD to 7 Seg Dcdr Drvr Open Coll
Learning Electronics Need to brush up on your electronics principles? A special two-part feature on how to use seven-segment alphanumeric displays. 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 rest of this article describes a few of the most popular of these devices. Figure 14 shows the functional diagram and pin notations of the B. Method of modifying the Figure 17 circuit to give automatic leading-zero suppression. Figure 3 shows how to connect the ripple-blanking terminals to give leading zero suppression on the first three digits of a four-digit display.
This feature enables the IC to act as a universal unit that can drive common-cathode or common-anode LED or liquid-crystal seven-segment displays with equal ease, as shown in Figures 10 to The B is very easy to use, and has only three input control terminals; of these, the not-LT pin 3 pin is normally tied high, but turns on all seven segments of the display when pulled low.
Figure 4 shows the functional diagram and pin notations of the device, which can use any power source in the 5V to 15V range. Basic way of using the B to drive a seven-segment common-cathode LED display. Enabling the display can be connected directly to the outputs of the IC without the use of external current-limiting resistors. Need to brush up on your electronics principles? This procedure is repeated on all except the LSD, which does not require zero suppression.
When the not-LATCH terminal is pulled low, the BCD input signals that are present at the moment of transition are latched into memory and fed in decoded form to the seven-segment outputs until the not-LATCH pin returns to the high state.
The B has four input control terminals, and three auxiliary output terminals. Figure 15 shows the basic circuit connections to be used when cascading stages.
The opening episode of this special feature explained the basic operating and usage principles of seven-segment alphanumeric displays. Some of these devices have integral ripple-blanking facilities, others have built-in data latches, and a few even have built-in decade counter stages, etc. In practice, however, it is far better to use a B IC for this particular application. 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.
Way of using the B to drive a seven-segment LCD. The display can be blanked at any time by driving the BL terminal to the logic-1 level. A current-limiting resistor Rx must be wired in series with each display segment and must have its value chosen 74ls447 limit the segment current below 25mA.