STMicroelectronics M74HC245B1R Octal Bus Transceiver

The M74HC245B1R is a high-speed CMOS octal bus transceiver manufactured by STMicroelectronics. Designed to be used in a variety of digital applications, this integrated circuit (IC) is part of the HC family, which ensures a balance between speed and power consumption, making it suitable for interfacing with both CMOS and TTL logic levels.

This transceiver is capable of bidirectional communication and is designed to improve the performance and flexibility of bus operations in a wide range of computing and networking applications. The M74HC245B1R allows for data flow in either direction, from A to B or B to A, depending on the logic level at the direction control (DIR) input. The output enable (OE) input can disable the device so that the buses are effectively isolated.

The device features eight non-inverting bus transceivers with 3-state outputs. The 3-state outputs ensure that multiple devices can share the same bus lines without interference. This is particularly useful in applications where multiple units need to send data over a single communication line, as it prevents any potential conflicts or data corruption.

Key specifications of the M74HC245B1R include:

• High-speed operation: t_PD = 8 ns (typical) at V_CC = 6V
• Low power dissipation: I_CC = 4 µA (maximum) at T_A = 25°C
• Compatible with TTL outputs: V_IH = 2V (minimum), V_IL = 0.8V (maximum)
• Pin and function compatible with 74 series logic
• Multiple package options

The M74HC245B1R is offered in a DIP-20 (Dual In-line Package) or SO-20 (Small Outline Package), providing flexibility for various PCB designs and space constraints. It operates over a broad voltage range from 2V to 6V and can handle continuous current up to ±35 mA at the outputs, allowing it to drive several devices simultaneously or interface with high-current loads.

With its robust design and the ability to operate in extreme temperature ranges, the M74HC245B1R is a reliable choice for critical communication interfaces in industrial, automotive, and consumer electronics applications. Its compatibility with other logic families also makes it an excellent choice for legacy system upgrades or mixed-technology environments.