The 'ALVTH16373 devices are 16-bit transparent D-type latches with 3-state outputs designed for 2.5-V or 3.3-V VCC operation, but with the capability to provide a TTL interface to a 5-V system environment. These devices are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.
These devices can be used as two 8-bit latches or one 16-bit latch. When the latch-enable (LE) input is high, the Q outputs follow the data (D) inputs. When LE is taken low, the Q outputs are latched at the levels set up at the D inputs.
A buffered output-enable (OE) input can be used to place the eight outputs in either a normal logic state (high or low logic levels) or a high-impedance state. In the high-impedance state, the outputs neither load nor drive the bus lines significantly. The high-impedance state and the increased drive provide the capability to drive bus lines without interface or pullup components.
OE does not affect internal operations of the latch. Old data can be retained or new data can be entered while the outputs are in the high-impedance state.
Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level.
When VCC is between 0 and 1.2 V, the device is in the high-impedance state during power up or power down. However, to ensure the high-impedance state above 1.2 V, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.
The SN54ALVTH16373 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74ALVTH16373 is characterized for operation from -40°C to 85°C.
State-of-the-Art Advanced BiCMOS Technology (ABT)WidebusTM Design for 2.5-V and 3.3-V Operation and Low Static Power Dissipation
Support Mixed-Mode Signal Operation (5-V Input and Output Voltages With 2.3-V to 3.6-V VCC)
Typical VOLP (Output Ground Bounce) < 0.8 V at VCC = 3.3 V, TA = 25°C
High Drive (-24/24 mA at 2.5-V and -32/64 mA at 3.3-V VCC)
Power Off Disables Outputs, Permitting Live Insertion
High-Impedance State During Power Up and Power Down Prevents Driver Conflict
Uses Bus Hold on Data Inputs in Place of External Pullup/Pulldown Resistors to Prevent the Bus From Floating
Auto3-State Eliminates Bus Current Loading When Output Exceeds VCC + 0.5 V
Latch-Up Performance Exceeds 250 mA Per JESD 17
ESD Protection Exceeds 2000 V Per MIL-STD-883, Method 3015; Exceeds 200 V Using Machine Model; and Exceeds 1000 V Using Charged-Device Model, Robotic Method