The maximum current that can be sourced or sunk by each output is 35mA, as specified in the datasheet. However, it's recommended to derate this value based on the ambient temperature and the number of outputs being driven.
To prevent damage from back-EMF, it's recommended to add a flyback diode (also known as a freewheeling diode) in parallel with the inductive load. This diode allows the current to continue flowing when the output is turned off, preventing the voltage from spiking and damaging the output transistors.
The minimum input voltage required for the SN75478P to function properly is 4.5V, as specified in the datasheet. However, it's recommended to use a voltage regulator to ensure a stable 5V supply to the device.
Yes, the SN75478P can be used to drive a relay, but the relay's coil current and voltage must be within the output current and voltage ratings of the device. Additionally, a flyback diode should be used to prevent back-EMF damage, and a current-limiting resistor may be required to prevent excessive current draw.
The output voltage of the SN75478P when driving a load depends on the input voltage, output current, and the internal voltage drop of the device. As a rough estimate, the output voltage can be calculated as Vin - 1.5V (typical voltage drop) - Iout * Rds(on) (output resistance). However, it's recommended to consult the datasheet and perform experiments to determine the actual output voltage for a specific application.
SN75478P datasheet
by Texas Instruments
