# Logic Design for Array-Based Circuits

### by Donnamaie E. White

Copyright © 1996, 2001, 2002 Donnamaie E. White

# Sizing the Design - Selecting the Array

Last Edit July 22, 2001

### Exercises

1. Select a semi-custom array series (any).
List:

• the processing technology
• available power supply configurations
• types of TTL input and outputs allowed
• types of ECL input and output allowed
• how bidirectional macros are handled

2. For the selected series, what cell usage restrictions exist?

• a. Any limits on inputs
• b. Any limits on outputs
• TTL
• ECL
• c. Any limits on bidirectionals
• d. Any rules for simultaneously switching outputs
• Are the rules easy to find?

3. For the selected series, how many fixed power and ground pads are on each array in the series? How are additional power and ground pads added?

4. For the selected series, what types of cells are available on each array and how many of each type?

5. How many internal cells would be required by the selected array series macros to implement an 8-bit barrel shift register (8 2:1 MUXs with 8 4:1 MUXs, 8 D flip/flops)?

6. Given a 16-bit fast adder design using carry-look ahead, 16 DATAA and 16 DATAB inputs, necessary controls (clock, reset, carry-in), a registered output, 17 outputs (sum plus carry out), size the design for the macro library for the selected array series. Assume a COMMERCIAL environment, single -5.2V power supply, ECL is ECL 10K or ECL 10KH.

Fast adder: four 4-bit fast adders with carry-propagate outputs; one 4-bit carry-look ahead unit; 17 D flip/flops; 35 ECL inputs; 17 outputs; buffers and gates as required; added power/ground as required.

7. Given a 32-bit register, 35 ECL inputs (32 data, clock, reset, 3-state enable), dual ECL-TTL outputs (32 TTL 3-state and 32 ECL, same signals), size the design for the selected array series. Assume a MILITARY environment, dual-power supplies of +5V and -5.2V, ECL is ECL 10K or ECL 10KH.

Register: 32 D flip/flops, 35 ECL inputs; 64 ECL outputs; buffers and gates as required; added power and ground as required.

Copyright @ 2001, 2002 Donnamaie E. White, White Enterprises
For problems or questions on these pages, contact dew@Donnamaie.com