I am thinking of powering the chips simply by voltage divider from 5 volts,
A few possibilities:
- See if you can power the chip at 5v. They may have maximum Vcc at 5v. Or they may be able to operate at 5v - you will need to see if you can take the changes.
- If you have to power it at a lower voltage, see if you can drop the 5v easier. Two silicon diodes in serial, plus a resistor to ground will provide about 1.4v drop; or a resistor to an LED (white LEDs for example are around 3v). or a zener.
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