SN54HC590A, SN74HC590A
8-BIT BINARY COUNTERS
WITH 3-STATE OUTPUT REGISTERS

SCLS039C - DECEMBER 1982 - REVISED MAY 1997

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

features

• 8-Bit Counter With Register
• High-Current 3-State Parallel Register Outputs Can Drive up to 15 LSTTL Loads
• Counter Has Direct Clear
• Package Options Include Plastic Small-Outline (D, DW), and Ceramic Flat (W) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs

description

The 'HC590A contain an 8-bit binary counter that feeds an 8-bit storage register. The storage register has parallel outputs. Separate clocks are provided for both the binary counter and storage register. The binary counter features direct clear () and count-enable () inputs. A ripple-carry output () is provided for cascading. Expansion is easily accomplished for two stages by connecting of the first stage to of the second stage. Cascading for larger count chains can be accomplished by connecting of each stage to the counter clock (CCLK) input of the following stage.

Both CCLK and the register clock (RCLK) input are positive-edge triggered. 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.

The SN54HC590A is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74HC590A is characterized for operation from -40°C to 85°C.