The ‘LS320 is a crystal-controlled oscillator/clock driver. It features complementary standard and high-current driver outputs. A synchronization flip-flop is included.
The driver outputs, F’ and F‘ have very-low impedance and can be used to drive highly capacitive TTL-level lines. If the driver outputs are not used, then the VCC‘ terminal can be left open.
The ‘LS321 is identical to the ‘LS320 except it additionally features two count-down outputs, F/2 and F/4.
These circuits were designed for crystal control of frequency and capacitive control is not recommended. If a fundamental crystal is used, an inductor of 5 to 160 μH is required to be connected between the tank 1 and tank 2 inputs.
Interaction of the driver outputs with the other outputs limits useful frequencies as shown in the frequency-limits table.
The SN54LS320 and SN54LS321 are characterized for operation over the full military temperature range of -55°C to 125°C. The SN74LS320 and SN74LS321 are characterized for operation from 0°C to 70°C.
Manufactured: 1986 week 36