LS7084

LSI/CSI UL ® LS7083/7084 (631) 271-0400 FAX (631) 271-0405 October 2000 LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 A3800 QUADRATURE CLOCK CONVERTER FEATURES: x1 and x4 mode selection Up to 16 MHz output clock frequency Programmable output clock pulse width On-chip filtering of inputs for optical or magnetic encoder applications. TTL and CMOS compatible I/Os +4.5V to +10.0V operation (VDD-VSS) LS7083, LS7084 (DIP) LS7083-S, LS7084-S (SOIC) - See Figure 1 DESCRIPTION: The LS7083 and LS7084 are monolithic CMOS silicon gate quadrature clock converters. Quadrature clocks derived from optical or magnetic encoders, when applied to the A and B inputs of the LS7083/LS7084, are converted to strings of Up Clocks and Down Clocks (LS7083) or to a Clock and an Up/Down direction control (LS7084). These outputs can be interfaced directly with standard Up/Down counters for direction and position sensing of the encoder. INPUT/OUTPUT DESCRIPTION: RBIAS (Pin 1) Input for external component connection. A resistor connected between this input and V SS adjusts the output clock pulse width (Tow). For proper operation, the output clock pulse width must be less than or equal to the A,B pulse separation (TOW≤TPS). VDD (Pin 2) Supply Voltage positive terminal. VSS (Pin 3) Supply Voltage negative terminal. A (Pin 4) Quadrature Clock Input A. This input has a filter circuit to validate input logic level and eliminate encoder dither. B (Pin 5) Quadrature Clock I...