Overview
The CD74HCT244 is a high-speed CMOS logic octal buffer/line driver produced by Texas Instruments. This component is part of the 74HCT series, which is compatible with TTL (Transistor-Transistor Logic) input levels. The CD74HCT244 is a non-inverting three-state buffer with two active-low output enables, making it suitable for a variety of digital logic applications.
This device is designed to operate over a wide temperature range from –55°C to 125°C and can handle high-current bus driver outputs, making it robust and reliable in diverse environments.
Key Specifications
| Parameter | Conditions | Unit | Min | Typ | Max |
|---|---|---|---|---|---|
| VCC (Supply Voltage) | V | 4.5 | 5.5 | ||
| VIH (High Level Input Voltage) | VCC = 5 V | V | 2 | ||
| VIL (Low Level Input Voltage) | VCC = 5 V | V | 0.8 | ||
| VOH (High Level Output Voltage) | IOH = –20 μA, VCC = 5 V | V | 4.4 | ||
| tPLH, tPHL (Propagation Delay) | CL = 15 pF, VCC = 5 V | ns | 9 | 22 | |
| tTHL, tTLH (Output Enable and Disable Time) | CL = 15 pF, VCC = 5 V | ns | 30 | 45 | |
| tTLH, tTHL (Output Transition Time) | CL = 15 pF, VCC = 5 V | ns | 12 | 18 | |
| CI (Input Capacitance) | pF | 10 | |||
| CO (Three-state Output Capacitance) | pF | 20 | |||
| CPD (Power Dissipation Capacitance) | pF | 40 |
Key Features
- Non-inverting Three-state Buffers: The CD74HCT244 features non-inverting buffers with two active-low output enables.
- High-Speed Operation: Typical propagation delay of 9 ns at VCC = 5 V and CL = 15 pF.
- Wide Operating Temperature Range: Operates from –55°C to 125°C.
- High-Current Bus Driver Outputs: Capable of driving up to 15 LSTTL loads.
- Three-state Outputs: Outputs can be set to a high-impedance state.
- Buffered Inputs: Reduces the load on the input signals.
- Low Power Consumption: Significant power reduction compared to LSTTL logic ICs.
- TTL Input Compatibility: Directly compatible with TTL input logic levels.
Applications
- Digital Logic Circuits: Ideal for use in digital logic circuits requiring high-speed buffering and line driving.
- Microprocessor and Microcontroller Systems: Used for interfacing and signal conditioning in microprocessor and microcontroller systems.
- Bus Systems: Suitable for driving high-capacity bus lines in various digital systems.
- Industrial Control Systems: Used in industrial control systems where high reliability and wide temperature range operation are necessary.
- Communication Equipment: Employed in communication equipment for signal buffering and amplification.
Q & A
- What is the typical propagation delay of the CD74HCT244?
The typical propagation delay of the CD74HCT244 is 9 ns at VCC = 5 V and CL = 15 pF.
- What is the operating temperature range of the CD74HCT244?
The CD74HCT244 operates over a temperature range from –55°C to 125°C.
- How many LSTTL loads can the CD74HCT244 drive?
The CD74HCT244 can drive up to 15 LSTTL loads.
- Does the CD74HCT244 have three-state outputs?
Yes, the CD74HCT244 features three-state outputs that can be set to a high-impedance state.
- Is the CD74HCT244 compatible with TTL input logic levels?
Yes, the CD74HCT244 is directly compatible with TTL input logic levels.
- What is the input capacitance of the CD74HCT244?
The input capacitance of the CD74HCT244 is 10 pF.
- What is the power dissipation capacitance of the CD74HCT244?
The power dissipation capacitance (CPD) of the CD74HCT244 is 40 pF.
- What are the package options available for the CD74HCT244?
The CD74HCT244 is available in SOIC, PDIP, and TSSOP packages.
- Can the CD74HCT244 be used in safety-critical applications?
No, the CD74HCT244 should not be used in safety-critical applications without proper evaluation and validation.
- What is the supply voltage range for the CD74HCT244?
The supply voltage range for the CD74HCT244 is from 4.5 V to 5.5 V.
