Overview
The SN74HC244N is an octal buffer and line driver integrated circuit produced by Texas Instruments. This device is designed to enhance the performance and density of 3-state memory address drivers, clock drivers, and bus-oriented receivers and transmitters. It is organized as two 4-bit buffers and drivers with separate output-enable (OE) inputs. When the OE input is low, the device passes noninverted data from the A inputs to the Y outputs. When the OE input is high, the outputs are in the high-impedance state, which is crucial for preventing bus contention and ensuring proper device operation during power-up or power-down phases.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage Range (VCC) | 2 | 6 | V | |
| Input Clamp Current (IIK) | ±20 | mA | ||
| Output Clamp Current (IOK) | ±20 | mA | ||
| Continuous Output Current (IO) | ±35 | mA | ||
| Junction Temperature (TJ) | 150 | °C | ||
| Storage Temperature (Tstg) | -65 | 150 | °C | |
| Low Power Consumption (ICC) | 80 | µA | ||
| Output Drive at 5 V | ±6 | mA | ||
| Input Current | 1 | µA | ||
| Propagation Delay Time (tpd) at VCC = 5 V | 11 | ns |
Key Features
- Wide operating voltage range of 2 V to 6 V
- High-current outputs drive up to 15 LSTTL loads
- 3-state outputs drive bus lines or buffer memory address registers
- Low power consumption: ICC, 80 µA (maximum)
- Typical propagation delay time (tpd) = 11 ns
- ±6 mA output drive at 5 V
- Low input current of 1 µA (maximum)
- Compliance with MIL-PRF-38535 for certain parameters
Applications
- Servers
- LED Displays
- Network Switches
- Telecom Infrastructure
- Motor Drivers
- I/O Expanders
Q & A
- What is the operating voltage range of the SN74HC244N?
The operating voltage range is from 2 V to 6 V.
- How many LSTTL loads can the SN74HC244N drive?
The SN74HC244N can drive up to 15 LSTTL loads.
- What is the purpose of the 3-state outputs in the SN74HC244N?
The 3-state outputs drive bus lines or buffer memory address registers.
- What is the maximum power consumption of the SN74HC244N?
The maximum power consumption is 80 µA.
- What is the typical propagation delay time (tpd) of the SN74HC244N at 5 V?
The typical propagation delay time is 11 ns.
- How much current can the SN74HC244N drive at 5 V?
The SN74HC244N can drive ±6 mA at 5 V.
- What is the maximum input current of the SN74HC244N?
The maximum input current is 1 µA.
- What are some common applications of the SN74HC244N?
Common applications include servers, LED displays, network switches, telecom infrastructure, motor drivers, and I/O expanders.
- How are the outputs of the SN74HC244N controlled?
The outputs are controlled by the output-enable (OE) inputs. When OE is low, the device passes data from the A inputs to the Y outputs. When OE is high, the outputs are in the high-impedance state.
- What should be done to ensure the high-impedance state during power-up or power-down?
The OE input should be tied to VCC through a pullup resistor to ensure the high-impedance state during power-up or power-down.
