JKNCF

Model

Truth Table

The JKCF or JKNCF handles asynchronous Set/Reset and synchronous JK transitions. It is negative-edge-triggered. Any prefix of JKCF or JKNCF can be used.

Note: JKPCF is the positive clock version, which triggers on the rising edge of C.

*Note: Set dominates when both NR and NS are low.

Timing Checks

Timing checks can be assigned by a TIMING-CHECKS block. Simic verifies the following constraints for JKCF:

• SETUP: Specifies the duration that an input must be stable prior to the active clock edge (fall).
  • SETUP.J, SETUP.K: Setup from J and K.
  • SETUP.NR: Setup from trailing edge of reset when logic-1 is clocked-in.
  • SETUP.NS: Setup from trailing edge of set when logic-0 is clocked-in.
• HOLD: Specifies the duration that an input must be stable after the active clock edge (fall).
  • HOLD.J, HOLD.K: Hold from J and K.
  • HOLD.NR: Hold from reset.
  • HOLD.NS: Hold from set.
• PULSE-WIDTHS: Specifies the minimum width of a pulse on control lines.
  • PW.NR, PW.NS: Pulse-width reset/set.
  • PW.C.H, PW.C.L: High and low pulse-width clock.

Unspecified timing checks default to 0 (disabled).

Example Usage

part=FF1 type=JKCF i=reset,set,clk,j,k o=q1 $
timing-checks= $
BEGIN; $
    SETUP = 5;      $ # All setups are 5 units
    HOLD.J = 10;    $ # Hold from J is 10
    HOLD = 5;       $ # All other holds are 5
    PW = 4;         $ # All pulse-widths are 4
    PW.C.L = 3;     $ # Clock-low pulse-width is 3
END;

Equivalent Type Statement

Type=JKNCF i=NR,NS,C,J,K o=Q
Type=JKCF i=NR,NS,C,J,K o=Q

Note: JKCF is an alias for JKNCF.