This is an SR flip-flop with universal gates at each input.
A D flip-flop is also connected to the outputs of the universal gates for additional flexibility.
The Q and Q-bar outputs of the SR and D flip-flops are all available at output pins.
The outputs of the universal gates, as well as the intermediate signals from the 2:1 muxs feeding the xor gates are also available at the outputs. This allows the circuit to be used as two independent universal gates, or multiplexers with both inverting and non-inverting outputs.
The universal gates are essentially the same circuit found in the 1G99 without the tri-state output.
This allows all the following functions to be implemented:
With the multiplexer output driven to a pin, the circuit can also implement a multiplexer with both inverting and non-inverting outputs:
The two universal gates are connected to an SR flip-flop and a D-type flip-flop as show below:
I'm not aware of many uses for a D flip-flop connected in parallel with a SR flip-flop. I expect only one to be connected at a time. Let me know if you come up with a use for both flip-flops simultaneously.
The universal gates on the flip-flop inputs allow for creating more feature rich flip-flops like this T-type flip-flop with clock enable:
The reason I included a SR flip-flop, and my primary purpose for this circuit is to implement the logic to drive a cyclops light from left and right tail light signals that you would find on a trailer connector. This circuit needs to turn on when both lights are on, and stay on until both are off, so that it does not blink with a turn signal. The cyclops configuration for the SR flip-flop is here:
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