Digital Logic Trainer is intended to study of BASIC Logic Gates, verification and it’s implementation techniques by experimentation. Using this trainer the students experiment, to verify the Boolean expressions for a given logic circuit. This involves the study of Karnaugh’s reduction techniques, combination logic designs, and application circuits in pursuit of understanding digital electronics.

This trainer is a self-contained instrument with all necessary facilities pooled in one instrument. It is desired to use Optional Digital multimeter and CRO as accessories for the measurement of voltages and observation of waveforms while performing experiment. The Front Panel of this instrument is well layed out with the representation of respective Boolean symbols for easy identification of Logic gates. The input and outputs of each logic circuit are terminated with silver-coated Phosphor Bronze springs for making multiple connections at any single spring terminal. The trainer is housed in an elegant and ergonomically designed cabinet with necessary power supplies, input / output facilities, signal sources. In all this is most suitable instrument for any DIGITAL ELECTRONICS LABORATORY.

Specifications:

Gates:

• 2 Input AND Gate – 4Nos
  
• 2 Input OR Gate – 4 Nos.
  
• NOT Gate – 6 Nos.
  
• 2 Input NAND Gate – 4 Nos.
  
• 2 Input EX-OR Gate – 4 Nos.
  
• 2 Input NOR Gate – 4 Nos
  
• JK-RS Flip Flop – 4Nos

Inputs:

• Logic Switch Inputs – 6 Nos.
  
• De-Bounced Pulser input – 1 No
  
• Free running TTL clock generator in Two ranges

Outputs:

• TTL Compatible Lamp indicators – 6 Nos.
  
• Independent 7 segment displays with decoders – 2 Nos.
  
• Power supply
  
• Built-In power supply 5V DC @ 1A

This is a 4 bit presetable CMOS ring counter, CD4029. This counter has

•UP Count facility, by switch selection
•DOWN Count facility by switch selection
•Preset a count in the range of 0000 to 1001 in case of DECIMAL count or from 0000 to 1111 in case of BINARY count. This is achieved by setting the 4bit PRESET state switches to either at 0 or at 1 state.
•Can be used as either a Straight Binary counter or DECIMAL counter.

Using the above counter any mode of operation can be set. A logic-1 output of this counter is used as gate trigger required for the SCR to go into active state. This in turn will act as a solid switch. A 230V AC operated Lamp load is used to display the state of the counter. In addition 4 bit LEDs will also display the status of this counter.

It is desirable to connect the gates together in as few a number as possible to create a desired output result given a fixed set of input conditions. Alternatively it may be necessary to utilize one type of gate to produce several other logic functions. Purchasing one IC type in bulk quantity has the advantage of reducing the cost of these chips. Two theories are used here. 1) Boolean Algebra. 2) De-morgans Theorem.

Specifications:

• NAND gate –6Nos
  
• OR gate –6 Nos
  
• NOR gate – 3 Nos
  
• INVERTERS –3Nos
  
• Binary Switch registers – 6Nos
  
• LED Indicators – 6 Nos
  
• Built-in Power supply.

These arithmetic logic units (ALU)/function generators perform 16 binary arithmetic operations on two 4-bit words. These operations are selected by the four function-select lines (S0, S1, S2, and S3) and include addition, subtraction, decrement and straight transfer. When performing arithmetic manipulations, applying a low-level voltage to the mode control input (M) must enable the internal carries. A full carry look-ahead scheme is available in these devices for fast, simultaneous carry generation by means of two cascade-outputs (P and G) for the four bits in the package. Using this demonstrator it is possible to perform and verify the following functions

• Two arithmetic operations: Addition and Subtraction of 4-bit binary words.
  
• Five logic operations: AND, NAND, OR, NOR, AND exclusive - OR.

In order to accomplish the above tasks, required address selector switches, DATA selector switches, push switches, LED indicators for ADDRESS and DATA are provided in the equipment itself. This trainer comes with necessary power supplies.

This demonstrator is intended to show how a RAM works. RAM is a device that is used to store the data. The RAM used here is a static RAM. If the power is switched OFF, the data stored will be fully erased. This demonstrator will provide a means to understand, what is ment by Selecting to set an address, Selecting to set a DATA, Write DATA in the memory, Read DATA so stored in the memory etc.

This trainer provides all the necessary input output devices like switches, LED indicators, momentary switches (debounced) etc. The block diagram shown on the front panel allows the student to view the DATA / Address and control logics.