I designed relay driver using TXB0108.
74HC238(Vcc 3.3V) -> (VccA 3.3V) TXB0108 (VccB 5V) -> ULN2003 -> Relay
But, TXB0108 is output voltage 2.5V to ULN2003.
I removed ULN2003. It is work fine.
How I solve problem.
plz help me.
For TXB0108, when you used it, you need to be careful for the pull up or pull down resistor adding, pull up or pull down resistor should be larger than 60kohms, based on the checking the datasheet of ULN2003, there are several pull down resistors which split the voltage output with pull up resistor(about 5kohms) inside the TXB0108.
So for TXB0108, it is not the suitable part for your design if you keep the ULN2003 with pull down resistor inside. we prefer you to use the SN74LVC8T245.
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