National Manuals

This document describes the TLF6561 DM74184 and DM74185A BCD-to-Binary and Binary-to-BCD Converters. These converters allow direct read-out of converted codes and demonstrate the versatility of read-only memory. The converters can be cascaded, have an overriding enable input, and open-collector outputs.

This is a synchronous reversible up-down counter with mode control. It is a 4-bit binary counter. Synchronous operation is achieved by clocking all flip-flops simultaneously, so that the outputs change simultaneously when instructed by the steering logic. This mode of operation eliminates the output counting spikes normally associated with asynchronous (ripple clock) counters. The outputs of the flip-flops are triggered on a low-to-high level transition of the clock input, if the enable input is low. A high enable input inhibits counting. Level changes at either the enable input or the down-up input should only be made when the clock input is high. The direction of the count is determined by the level of the down-up input. When low, the counter counts up, and when high, it counts down. This counter is fully programmable, meaning the outputs can be preset to any level by placing a low on the load input and entering the desired data at the data inputs. The output will change independent of the level of the clock input. This feature allows the counters to be used as modulo-N dividers by modifying the count length with the preset inputs. The clock, down-up, and load inputs are buffered to lower the drive requirement, which significantly reduces the drive requirement.

5420 Dual 4-Input NAND Gates is a digital integrated circuit produced by National Semiconductor Corporation. It can perform logic NAND function.

DM7427 is a triple 3-input NOR gate from National Semiconductor

This document describes a Quad Set-Reset Latch device called TL�F�9785 54279�DM74279, which contains four independent set-reset type flip-flops with one Q output each. The device has the characteristics of high-level output, low-level output, and indeterminate output.

The 54283 is a 4-bit binary full adder with internal carry lookahead manufactured by National Semiconductor Corporation. It accepts two 4-bit binary numbers (A0-A3 B0-B3) and a carry input (C0), and generates binary sum outputs (S0-S3) and carry output (C4) from the most significant bit. It also works with active high or active low operands (positive or negative logic)

5437�DM5437�DM7437 Quad 2-Input NAND Buffers is a circuit device released by National Semiconductor Corporation, which has four independent gates, each of which performs the logic NAND function.

DM7439 is a digital logic chip produced by National Semiconductor Corporation. It contains 4 independent gates, each with 2 data inputs, and each gate performs the logic NAND function.

5442A�DM5442A�DM7442A BCD to Decimal Decoders is a logic circuit device produced by National Semiconductor.

This document describes the features and characteristics of TL6517 DM5445 DM7445 BCD-to-decimal decoders-drivers. It consists of eight inverters and ten four-input NAND gates, which are used to decode BCD input data into outputs. Full decoding of BCD input logic ensures that all outputs remain off for all invalid (10-15) binary input conditions. These decoders feature high-performance NPN output transistors designed for use as indicator-relay drivers or as open-collector logic-circuit drivers. The high-breakdown output transistors are compatible for interfacing with most MOS integrated circuits.