7407 Hex Buffer, High voltage Open collector in Pakistan

This circuit is a synchronous up/down 4-bit binary counter. Synchronous operation is provided by having all flip-flops clocked simultaneously so that the outputs change together when so 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 four master-slave flip-flops are triggered by a low-to-high level transition of either count (clock) input. The direction of counting is determined by which count input is pulsed while the other count input is held high. The counter is fully programmable; that is, each output may be preset to either level by entering the desired data at the inputs while the load input is low. The output will change independently of the count pulses.

These are high-speed silicon-gate CMOS decoders well suited to memory address decoding or data-routing applications. Both circuits feature low power consumption usually associated with CMOS circuitry, yet have speeds comparable to low-power Schottky TTL logic. Both circuits have three binary select inputs (A0, A1, and A2). If the device is enabled, these inputs determine which one of the eight normally high outputs of the HC/HCT138 series goes low or which of the normally low outputs of the HC/HCT238 series go high. Two active low and one active high enables (E1, E2, and E3)are provided to ease the cascading of decoders. The decoder’s eight outputs can drive ten low-power Schottky TTL equivalent loads.

This Data Selector/Multiplexer contains full on-chip decoding to select one-of-eight data sources as a result of a unique three-bit binary code at the Select inputs. Two complementary outputs provide both inverting and non-inverting buffer operation. A Strobe input is provided which, when at the high level, disables all data inputs and forces the Y output to the low state and the W output to the high state. The Select input buffers incorporate internal overlap features to ensure that select input changes do not cause invalid output transients. RoboticsBD