Overview
The SN74HCT574DBR, produced by Texas Instruments, is an octal edge-triggered D-type flip-flop integrated circuit. This device is designed with 3-state outputs, making it particularly suitable for bus driving applications. It operates within a voltage range of 4.5V to 5.5V and is compatible with TTL (Transistor-Transistor Logic) voltage levels. The flip-flops are triggered on the low-to-high transition of the clock input, and the outputs can be placed in a high-impedance state using the output enable (OE) input. This feature allows the outputs to neither load nor drive the bus lines significantly, enhancing the device's versatility in various digital circuit designs.
Key Specifications
| Parameter | Min | Max | Unit | |
|---|---|---|---|---|
| Supply Voltage (VCC) | 4.5 | 5 | 5.5 | V |
| High-Level Input Voltage (VIH) | 2 | - | - | V |
| Low-Level Input Voltage (VIL) | - | - | 0.8 | V |
| Output Voltage (VOH) at IOH = -20 μA | 4.4 | - | - | V |
| Output Voltage (VOH) at IOH = -6 mA | 3.7 | - | - | V |
| Output Voltage (VOL) at IOL = 20 μA | 0.1 | - | - | V |
| Output Voltage (VOL) at IOL = 6 mA | 0.4 | - | - | V |
| Propagation Delay Time (tpd) at CL = 50 pF | 25 | 32 | 48 | ns |
| Maximum Clock Frequency (fmax) at CL = 50 pF | 22 | - | 27 | MHz |
| Operating Free-Air Temperature (TA) | -40 | - | 85 | °C |
Key Features
- Operating voltage range of 4.5V to 5.5V
- High-current 3-state noninverting outputs capable of driving bus lines directly or up to 15 LSTTL loads
- Low power consumption, with a maximum ICC of 80 μA
- Typical propagation delay time (tpd) of 22 ns
- ±6 mA output drive at 5V
- Low input current of 1 μA max
- TTL-voltage compatible inputs
- Bus-structured pinout for easy integration into bus-driven systems
- Output enable (OE) input to control the output state (normal logic or high-impedance)
Applications
The SN74HCT574DBR is particularly suitable for various digital circuit applications, including:
- Implementing buffer registers
- Designing I/O ports
- Creating bidirectional bus drivers
- Building working registers
Q & A
- What is the operating voltage range of the SN74HCT574DBR?
The operating voltage range is 4.5V to 5.5V.
- What is the maximum propagation delay time (tpd) of the SN74HCT574DBR?
The typical propagation delay time is 22 ns, with a maximum of 48 ns at CL = 50 pF.
- How many LSTTL loads can the outputs drive?
The outputs can drive up to 15 LSTTL loads.
- What is the maximum clock frequency (fmax) of the SN74HCT574DBR?
The maximum clock frequency is 27 MHz at CL = 50 pF.
- What is the purpose of the output enable (OE) input?
The OE input can place the outputs in either a normal logic state or a high-impedance state.
- What are the typical applications of the SN74HCT574DBR?
It is used for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.
- What is the package type of the SN74HCT574DBR?
The device is available in various packages including SSOP, SOIC, PDIP, SO, and TSSOP.
- Is the SN74HCT574DBR RoHS compliant?
Yes, the device is RoHS compliant.
- What is the operating free-air temperature range of the SN74HCT574DBR?
The operating free-air temperature range is -40°C to 85°C.
- How does the device handle unused inputs?
All unused inputs must be held at VCC or GND to ensure proper device operation.
