Overview
The SN74HCT244N is an octal buffer and line driver produced by Texas Instruments. This device is part of the 74HCT series, which is designed to improve the performance and density of 3-state memory address drivers, clock drivers, and bus-oriented receivers and transmitters. The SN74HCT244N operates within a voltage range of 4.5 V to 5.5 V and is organized as two 4-bit buffers or drivers with separate output-enable (OE) inputs. When the OE input is low, the device passes non-inverted data from the A inputs to the Y outputs, and when the OE input is high, the outputs are in the high-impedance state.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC Supply Voltage | 4.5 | 5 | 5.5 | V |
| VIH High-Level Input Voltage | 2 | V | ||
| VIL Low-Level Input Voltage | 0.8 | V | ||
| IOH Output Current (High) | -20 µA | -6 mA | A | |
| IOL Output Current (Low) | 20 µA | 6 mA | A | |
| ICC Supply Current | 8 | 80 | 160 | µA |
| tpd Propagation Delay (A to Y) | 13 | 25 | 38 | ns |
| TJ Junction Temperature | 150 | °C |
Key Features
- Operating voltage range of 4.5 V to 5.5 V
- High-current outputs drive up to 15 LSTTL loads
- Low power consumption: 80-µA maximum ICC
- Typical propagation delay (tpd) of 13 ns
- ±6-mA output drive at 5 V
- Low input current of 1 µA maximum
- Inputs are TTL-voltage compatible
- 3-state outputs drive bus lines and buffer memory address registers
Applications
- Servers
- LED displays
- Network switches
- Telecom infrastructure
- Motor drivers
- I/O expanders
Q & A
- What is the operating voltage range of the SN74HCT244N?
The operating voltage range is from 4.5 V to 5.5 V.
- How many LSTTL loads can the SN74HCT244N drive?
The device can drive up to 15 LSTTL loads.
- What is the typical propagation delay of the SN74HCT244N?
The typical propagation delay (tpd) is 13 ns.
- What is the maximum supply current (ICC) of the SN74HCT244N?
The maximum supply current (ICC) is 80 µA.
- What are the input voltage levels for the SN74HCT244N?
The high-level input voltage (VIH) is 2 V, and the low-level input voltage (VIL) is 0.8 V.
- How do the 3-state outputs function in the SN74HCT244N?
The 3-state outputs can be in a high-impedance state, low, or high, controlled by the output-enable (OE) input.
- What are some common applications of the SN74HCT244N?
Common applications include servers, LED displays, network switches, telecom infrastructure, motor drivers, and I/O expanders.
- What is the junction temperature range for the SN74HCT244N?
The junction temperature range is up to 150 °C.
- How does the output-enable (OE) input affect the outputs of the SN74HCT244N?
When the OE input is low, the device passes data from the A inputs to the Y outputs. When the OE input is high, the outputs are in the high-impedance state.
- What is the electrostatic discharge (ESD) rating for the SN74HCT244N?
The ESD rating is ±2000 V for the human-body model (HBM) and ±1000 V for the charged-device model (CDM).
