The SN74F109N is a Texas Instruments dual JK flip-flop in the 74F bipolar logic family, packaged in a 16-pin PDIP (0.300-inch width) for through-hole assembly. Each of the two elements is a single-bit, positive-edge-triggered JK flip-flop with complementary outputs and separate Set (Preset) and Reset inputs, giving the designer independent control over initialisation state. The 150 MHz maximum clock frequency sets the upper toggle rate — at this speed the 8 ns propagation delay at 5V, 50 pF load consumes roughly 1.2 clock periods in flight, so cascaded stages need a timing margin check at the system level.
Supply voltage is 4.5V to 5.5V — this is a 5V-only bipolar part; it does not operate from 3.3V or lower rails without a level translator on the inputs and outputs. Quiescent current is 17 mA typical, and the output drive capability is 1 mA source / 20 mA sink — sufficient for driving one or two standard TTL loads but not high-fanout buses without buffering.