The maximum frequency of operation for the M74HC138TTR is typically around 25 MHz, but it can vary depending on the specific application and operating conditions. It's recommended to consult the datasheet and perform simulations to determine the maximum frequency for a specific design.
To ensure proper power and decoupling, it's recommended to follow the guidelines in the datasheet and application notes. Typically, this includes using a stable power supply, decoupling capacitors (e.g., 0.1 uF and 10 uF) close to the device, and ensuring that the power pins are properly connected and bypassed.
The recommended layout and routing for the M74HC138TTR involves keeping the signal traces short and direct, avoiding sharp corners and vias, and using a solid ground plane to reduce noise and EMI. It's also recommended to follow the guidelines in the datasheet and application notes, and to use simulation tools to optimize the layout and routing.
The enable inputs (E1, E2, and E3) in the M74HC138TTR are active-low, meaning that they must be driven low to enable the device. It's recommended to use a pull-up resistor (e.g., 1 kΩ) to ensure that the enable inputs are properly biased, and to use a logic level translator if necessary to match the voltage levels of the enable signals.
The maximum current that the M74HC138TTR can sink or source depends on the specific pin and operating conditions. According to the datasheet, the maximum output current is typically around 25 mA per pin, but it's recommended to consult the datasheet and perform simulations to determine the maximum current for a specific design.
M74HC138TTR datasheet
by STMicroelectronics
