74VCX16500

74VCX16500 Low Voltage 18-Bit Universal Bus Transceivers with 3.6V Tolerant Inputs and Outputs March 1998 Revised April 1999 74VCX16500 Low Voltage 18-Bit Universal Bus Transceivers with 3.6V Tolerant Inputs and Outputs General Description The VCX16500 is an 18-bit universal bus transceiver which combines D-type latches and D-type flip-flops to allow data flow in transparent, latched, and clocked modes. Data flow in each direction is controlled by output-enable (OEAB and OEBA), latch-enable (LEAB and LEBA), and clock (CLKAB and CLKBA) inputs. For A-to-B data flow, the device operates in the transparent mode when LEAB is HIGH. When LEAB is LOW, the A data is latched if CLKAB is held at a HIGH or LOW logic level. If LEAB is LOW, the A bus data is stored in the latch/flip-flop on the HIGH-to-LOW transition of CLKAB. When OEAB is HIGH, the outputs are active. When OEAB is LOW, the outputs are in a highimpedance state. Data flow for B to A is similar to that of A to B but uses OEBA, LEBA, and CLKBA. The output enables are complementary (OEAB is active HIGH and OEBA is active LOW). Features s 1.65V–3.6V VCC supply operation s 3.6V tolerant inputs and outputs s tPD (A to B, B to A) 2.9 ns max for 3.0V to 3.6V VCC 3.5 ns max for 2.3V to 2.7V VCC 7.0 ns max for 1.65V to 1.95V VCC s Power-down high impedance inputs and outputs s Supports live insertion/withdrawal (Note 1) s Static Drive (IOH/IOL) ±24 mA @ 3.0V VCC ±18 mA @ 2.3V VCC ±6 mA @ 1.65V VCC s Uses patented noise/EMI reducti...