Patent ID: 6801069
Filing Date: 2004-10-05
Classification: H03K

Abstract:
A receiving latch with hysteresis circuit for receiving data on cross chip boundaries in a chip to chip interface, comprising a receiver enable input pin (E), a data line (D to L1), a receiver latch circuit section including a receiver feed section (20,115,119,120), a clock section (30) and a hysteresis latch (40,114,114â€² 114â€³,116,116â€²,116â€³,117,118) having a pass gate (114), configured so that said receiver enable input pin (E) is settable to a high (Data ON) or low (Data OFF) voltage level to set the hysteresis for the receiver latch circuit section and also to gate any input data at a data input pad (D) to the data line setting the hysteresis of the receiver latch circuit section when the voltage level at said enable input pin (E) goes high, and wherein a clock signal is supplied by the clock section of said receiver latch circuit section, and said receiver feed section supplies a data line output (DN) of said receiver feed section to the hysteresis latch having said pass gate (114), and wherein said hysteresis latch with the pass gate has clock couplings to a pgate and an ngate of a pass gate PFET (114â€²) and a pass gate NFET (114â€³) transistor of the pass gate (114), respectively, with the drains of said pass gate PFET (114â€²) and pass gate NFET (114â€³) being coupled to ground via hysteresis latch NFET (118) of said hysteresis latch and with the sources of said pass gate PFET (114â€²) and pass gate NFET (114â€³) coupled to the input data line via the data line output (DN) of said receiver feed section, the drain of a hysteresis latch PFET (117) of said hysteresis latch having its source connected to a positive potential and the source of said hysteresis latch NFET (118) having its drain connected to ground and both said hysteresis latch PFET (117) and said hysteresis latch NFET (118) having their gate connection to a data line latch output (L1) for gating the data line information out of the hysteresis latch (40).