What is the function of IC 74138?

Table of Contents

74138 is used to generate chip signals.

What is a 74138 decoder?

IC 74138 is a Logical Decoder IC. It also has a demultiplexing facility. The IC 74138 is available in the market with the name of 74LS138. It is a 3 to 8 decoder IC. The internal circuit of this IC is made of high-speed Schottky barrier diode.

Which IC used in decoder?

The decoder 74LS138 IC uses advanced technology like silicon (Si) gate TTL technology. These are suitable for different applications like memory address decoding otherwise data routing.

What is difference between decoder and demux?

No. A Decoder decodes an encrypted input signal to multiple output signals from one format to another format. A De-Multiplexer routes an input signal to multiple output signals.

What is the significance of Enable strobe signal?

It’s often desirable to add an enable (or strobe) input EN to a multiplexer. An enable input makes the multiplexer operate. When EN = 0, the output is High-Z or less commonly LOW (depending on the specific device). When EN = 1, the multiplexer performs its operation depending on the selection line.

What is the function of Enable pin in a decoder?

Some binary decoders have an additional input pin labelled “Enable” that controls the outputs from the device. This extra input allows the decoders outputs to be turned “ON” or “OFF” as required.

What will be the output of 74138 decoder IC for all input at high state when enabled pin high?

The enable pins are two active low & one active high. The output of the decoder can drive 10 low-power Schottky TTL equal loads, and all the inputs are defended from harm because of static discharge with diodes toward VCC as well as the ground. This article discusses an overview of 74LS138 IC:3 to 8 Line Decoder IC.

How many 74LS138 decoders are required to generate CS signals?

The 74LS138 requires 12ns to decode. The 8088 runs at 5MHz and only allows 460ns for memory to access data. A wait state adds 200ns of additional time.

What is decoder in digital system?

The name “Decoder” means to translate or decode coded information from one format into another, so a digital decoder transforms a set of digital input signals into an equivalent decimal code at its output.

Where is decoder used?

Amongst its many uses, a decoder is widely used to decode the particular memory location in the computer memory system. Decoders accept the address code generated by the CPU which is a combination of address bits for a specific location in the memory.

What is IC 74138?

How many decoders do we take in 74138?

We take the popular 3 to 8 decoder Integrated Circuit 74138. The Integrated Circuit is of 16 pins. We have three input pins which are actively in high state and are classified as I 2, I 1 and I 0.

How many binary input signals can IC 74138 take?

So the IC 74LS138 can take three binary input signals. 3. There are three enable input pins E1, E2, E3 (pin no. 4, 5, 6). E1 and E2 are the active LOW pins that mean when low signals are applied to those pins they will be active. 4. Pin no. 7 and 9 to 15 are the output pins. The logical circuit of the IC 74138 is made using NOT Gate, and AND Gates.

What type of power supply is needed for the 74138?

A power supply of +5 V DC is needed by the chip and is Grounded. Fig. Diagram in functional mode of 74138 The point to be noted that, only one of the lines of output which completely depends on the input pins I 2, I 1, and I 0.