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SN74HCS04: Can Inverter driven using negative VCC?

Part Number: SN74HCS04
Other Parts Discussed in Thread: SN74LVC2G14, TL331, TLV1701

I need to construct a logic bias driver circuit for an a RF SPDT switch.

It negative signal two differentiate logic high and logic low. 

The logic requirement is (low= 0V~ -0.5V , high= -3V~ -7V)

The recommended driver circuit is as below. 

Can SN74HCS04 driven by a negative supply? Will it produce the state high, low as above?



  • The SN74HCS04 (like other logic gates) requires that the voltage difference between its VCC and GND pins is at most 5 V, and, most importantly, that the voltages at its input and output pins is between these. The 5.1 V Zener diode indeed ensures that these requirements are met by shifting the input signal down. (Instead of the SN74HCS04, you could also use the two-channel SN74LVC2G14.)

    Alternatively, generate the negative signal with a 10 V comparator with an open-drain output, e.g., TL331(B) or TLV1701: