SN74LVC574A中文资料具有三态输出的八路边沿触发式 D 型触发器数据手册TI规格书

描述 Description

The SN54LVC574A octal edge-triggered D-type flip-flop is designed for 2.7-V to 3.6-V VCC operation, and the SN74LVC574A octal edge-triggered D-type flip-flop is designed for 1.65-V to 3.6-V VCC operation.

These devices feature 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads. They are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.

On the positive transition of the clock (CLK) input, the Q outputs are set to the logic levels at the data (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 the high-impedance state. In the high-impedance state, the outputs neither load nor drive the bus lines significantly. The high-impedance state and increased drive provide the capability to drive bus lines without interface or pullup components.

OE\\ does not affect the internal operations of the flip-flops. Old data can be retained or new data can be entered while the outputs are in the high-impedance state.

These devices are fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.

To ensure the high-impedance state during power up or power down, 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.

Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of these devices as translators in a mixed 3.3-V/5-V system environment.

特性 Features

• Operate From 1.65 V to 3.6 V
• Inputs Accept Voltages to 5.5 V
• Specified From -40°C to 85°C, -40°C to 125°C, and -55°C to 125°C
• Max tpd of 7 ns at 3.3 V
• Typical VOLP (Output Ground Bounce)    CC = 3.3 V, TA = 25°C
• Typical VOHV (Output VOH Undershoot)    >2 V at VCC = 3.3 V, TA = 25°C
• Support Mixed-Mode Signal Operation on All Ports (5-V Input/Output Voltage With 3.3-V VCC)
• Ioff Supports Partial-Power-Down Mode Operation
• Latch-Up Performance Exceeds 250 mA Per JESD 17
• ESD Protection Exceeds JESD 22
• 2000-V Human-Body Model (A114-A)
• 200-V Machine Model (A115-A)
• 1000-V Charged-Device Model (C101)