MC100H640

www.DataSheet4U.com MOTOROLA SEMICONDUCTOR TECHNICAL DATA 68030/040 PECL-TTL Clock Driver The MC10H/100H640 generates the necessary clocks for the 68030, 68040 and similar microprocessors. It is guaranteed to meet the clock specifications required by the 68030 and 68040 in terms of part–to–part skew, within–part skew and also duty cycle skew. The user has a choice of using either TTL or PECL (ECL referenced to +5.0V) for the input clock. TTL clocks are typically used in present MPU systems. However, as clock speeds increase to 50MHz and beyond, the inherent superiority of ECL (particularly differential ECL) as a means of clock signal distribution becomes increasingly evident. The H640 also uses differential PECL internally to achieve its superior skew characteristic. The H640 includes divide–by–two and divide–by–four stages, both to achieve the necessary duty cycle skew and to generate MPU clocks as required. A typical 50MHz processor application would use an input clock running at 100MHz, thus obtaining output clocks at 50MHz and 25MHz (see Logic Symbol). The 10H version is compatible with MECL 10H™ ECL logic levels, while the 100H version is compatible with 100K levels (referenced to +5.0V). MC10H640 MC100H640 68030/040 PECL–TTL CLOCK DRIVER Generates Clocks for 68030/040 Meets 030/040 Skew Requirements TTL or PECL Input Clock Extra TTL and PECL Power/Ground Pins Asynchronous Reset Single +5.0V Supply FN SUFFIX PLASTIC PACKAGE CASE 776–02 Function Reset...