NXP 74HC590D,112 芯片, 纹波二进制计数器, 61MHZ, SOIC-16
The 74HC590D is a 8-bit Binary Counter with a storage register and 3-state outputs. The storage register has parallel Q0 to Q7 outputs. The binary counter features master reset counter MRC\\ and count enable CE\\ inputs. The counter and storage register have separate positive edge triggered clock CPC and CPR inputs. If both clocks are connected together, the counter state is always one count ahead of the register. Internal circuitry prevents clocking from the clock enable. A ripple carry output RCO\\ is provided for cascading. Cascading is accomplished by connecting RCO\ of the first stage to CE\ of the second stage. Cascading for larger count chains can be accomplished by connecting RCO\ of each stage to the counter clock CPC input of the following stage. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC.