Abstract:
A quadrature output (IP, IN, QP, QN) high-frequency RF divide-by-two circuit (129) includes a pair of differential complementary logic latches (142, 143). The latches are interconnected to form a toggle flip-flop (200). Each latch (200) includes a tracking cell and a locking cell. In a first embodiment (200), the locking cell includes two complementary logic inverters (201, 205, 203, 207) and two transmission gates (202, 206; 204, 208). When the locking cell is locked, the two gates (211, 213; 212, 214) are enabled such that the locked (i.e., latched) signal passes through both transmission gates and both inverters. In one advantageous aspect, the tracking cell only involves two transmission gates (211, 213; 212, 214). Due to the circuit topology, the first embodiment is operable from a low supply voltage at a high operating frequency while consuming a low amount of supply current. In a second (300) and third embodiment (400), the tracking cell involves a pair of inverters ((301, 304; 302, 305) or (401, 404; 402, 405)). The sources of the transistors of the inverters are, however, coupled together thereby resulting in performance advantages over conventional circuits.
Abstract:
A latching element (124) latches incoming data (D(7:0)) into an integrated circuit (101). The latching element (for example, a latch or flip-flop) can be considered to include a data path portion (126), a clock path portion (127), and an ideal latching element (125). In one embodiment, an open-loop replica (118) of the data path portion (126) is disposed in a clock signal path between a clock input terminal (116) of the integrated circuit and a clock input lead (130) of the latching element. In a second embodiment, an additional replica (144) of the clock path portion is disposed in a data signal path between a data terminal (105) of the integrated circuit (101) and a data input lead (128) of the latching element. The replica circuits (118,144) help prevent changes in skew between a data path propagation time to the ideal latching element and clock path propagation time to the ideal latching element. Setup times remain substantially constant over PVT (process, supply voltage, temperature).
Abstract:
A clip for engaging tissue includes a generally annular-shaped body defining a plane and disposed about a central axis extending normal to the plane. The body includes alternating inner and outer curved regions, defining a zigzag pattern about a periphery of the clip. The body is biased towards a planar configuration lying in the plane and deflectable towards a transverse configuration extending out of the plane. Tines extend from the inner curved regions, the tines being oriented towards the central axis in the planar configuration, and parallel to the central axis in the transverse configuration. The tines may include primary tines and secondary tines that are shorter than the primary tines. The primary tines may be disposed on opposing inner curved regions and oriented towards one another such that they overlap in the planar configuration.
Abstract:
A flip-flop includes an input stage to receive a data signal and an output stage to provide an output signal. A clock input is directly connected to a transmission gate of the output stage and coupled by way of a delay circuit to a transmission gate of the input stage. A first latch is coupled between the transmission gate of the input stage and the output stage.
Abstract:
Output logic macrocells (504) for a programmable logic device as well as a block clock/control circuit (502) which allocates multiple clock signals (CK1-CKN) to each macrocell. Each macrocell includes a multiplexer (506) selectively providing one of the multiple clock signals to a clock input of a storage element (508), which operates similar to a latch. The storage element further receives a sum of product terms output from an OR gate at its data input. Vcc may be provided through the multiplexer to enable the storage element to function in a combinatorial mode. The multiple clock signals may include a clock signal provided to the multiplexer to enable the storage element to function in a latch mode. The clock signal may also be provided through a pulse generator in the block clock/control circuit to provide pulses having a pulse width delta to enable the storage element to function in a D-type flip-flop mode. For the D flip-flop mode, the storage element may be configured to operate as a P-type flip-flop so that its output will change states to follow its data input at a leading edge of its clock input, then does not change states for a period epsilon , wherein epsilon > delta , and then its output will change states to match its data input after the period epsilon if a signal received at the clock input has a period greater than epsilon . To provide reset or preset, a reset or preset signal may be provided at the data input of the storage element, as well as through a second pulse generator in the block clock/control circuit to the clock input of the storage element. The block clock/control circuit may be further configured to provide a dual edge clock mode, a mixed clock mode wherein two signals are provived on a single clock line, or other clocking modes.
Abstract:
Embodiments of a flip-flip circuit are disclosed that may allow a reduction in data setup time and lower switching power. The flip-flop circuit may include an input circuit, an output circuit, a clock circuit, and a feedback circuit. The clock circuit may be operable to generate internal clocks dependent upon received data, and the generated internal clocks may enable the feedback and input circuits.
Abstract:
A flip-flop having a first storage circuit having a first input fed by the true logic signal and a second input fed by the complement of the logic signal. A second storage circuit has a pair of inputs coupled to the first storage circuit. In response to one clock signal: the first storage circuit passes the true and complement logic signals for storage therein while the second storage circuit prevents the true and complement logic signals stored in the first storage circuit from passing to the second circuit. In response to a subsequent clock signal; the first storage circuit prevents the true and complement logic signals from passing for storage in the first storage circuit while the second storage circuit passes the true and complement logic signals stored in the first storage circuit at the outputs of the first storage circuit to the second storage circuit for storage therein.
Abstract:
A circuit (10) has first latch (30), a second latch (32), a coupling circuit (39), and a power down circuit (34). The first latch (30) has an input/output coupled to a data node (27). The second latch (32) has an input/output. The coupling circuit (39) is coupled between the input/output of the second latch (32) and the data node (27). The coupling circuit (39) is enabled during a normal operation of the circuit (10) and disabled during a power down mode of the circuit (10). The power down control circuit (34) is for disabling the first latch (30) during the power down mode and for a time period after a transition from the power down mode to the normal operation. This allows the second latch (32) to set the state of the first latch (30) when transitioning from the power down mode to the normal mode. Thus normal operation can be fast, and the power down mode can have low leakage current.