摘要:
A frequency divider providing an odd integer division factor comprising a binary counter (10) providing an even integer division factor, which is the first even number smaller than the odd division factor, the binary counter having a clock input for receiving a periodical clock signal (Ck) having a frequency. The circuit further comprises an end of count circuit (20) coupled to the binary counter and generating an End Of Count signal (EOC) for a clock (Ck) period after every even integer number periods of the clock signal (Ck), the end of count signal (EOC) being inputted to an input (IN) of the counter (10). The circuit further includes an output generator (30) coupled to the binary counter and to the clock signal (Ck), the output generator (30) generating an output signal (OUT) having a frequency which is substantially equal with the frequency of the frequency signal (Ck) divided by the odd division factor.
摘要:
A synchronous binary counter (30) has a plurality of stages (20A,20B), each with a number of synchrounously clocked flipflops (21 to 23) and combinational logic (24 to 26) for determining the states of these flipflops following their next clocking. Each stage (20B), other than the first, receives a carry signal from a preceding stage (20A). In order to avoid the carry signals passed to later stages (20B) being subject to excessive ripple-through delays in the combinatinal logic (24A, 25A, 26A) in the preceding stages (20A), the carry signal passed from one stage to another is delayed by a delayed-carry circuit (31) such that it is input to the receiving stage (20B) at the start of the clock period following that in which it was generated by the outputting stage (20A). This enables any number of counter stages to be serially interconnected without problems caused by signal delay in the combinational logic.
摘要:
Digital counter register stages RCRG(N) are constructed as two-to-one mux registers, each employing a multiplexer stage (113) having first, second, and third inputs (S0, I0, I1) and an output (116) connected to the switching signal input (D) of a D-type flip-flop (15), whose Q output comprises a first input (I1) to the multiplexer stage (113). An inverter buffer (19) is associated with each register stage (RCRG(N)) and has an input connected to the output (Q) of said D-type flip-flop (115) and an output connected to the second input (I0) of the multiplexer stage (RCRG(N)) and fed forward to a NOR gate (21) associated with each subsequent register stage (RCRG(N)).
摘要:
An image pickup apparatus includes a lens, and a solid-state image sensor for converting light which passes through the lens into an electric signal. A signal processing circuit serves to process the electric signal outputted from the solid-state image sensor. A Gray code counter serves to count pulses of a first clock signal and to generate Gray codes in response to the first clock signal. A device functions to feed a second clock signal and a synchronizing signal to the solid-state image sensor and the signal processing circuit in response to the Gray codes generated by the Gray code counter respectively. A counter circuit includes n-bit counting stages where n denotes a predetermined natural number, and a plurality of logic decoders for feeding logic outputs to input terminals of the respective counting stages, the logic outputs being equivalent to a product of a first logic output of a (k-1)-th-bit counting stage and second logic outputs of a (k-2)-th-bit counting stage and lower-bit counting stages where k denotes a natural number between 3 and n.
摘要:
A high speed counter circuit for counting electrical pulses includes a master/slave flip-flop at the input stage of the counter. An AND gate logically ANDs the pulses being counted with the master output to produce a first gating signal. A plurality of cascade coupled flip-flops each having a slave and an inverse slave output are provided. The clock input to each cascade coupled flip-flop is produced by the logical OR of the electrical pulses being counted, the first gating signal and the slave output of all preceding flip-flops of the counter. The counter output is provided by the inverse slave output of each flip-flop.
摘要:
An M-bit binary counter is disclosed having M sequentially ascending binary value stages, the first stage being the lowest significant bit. Each stage above the least significant bit stage has a subsequent value decoder (100) which has the function of determining the effect of lower order carry bits on higher order stages with a minimum of signal delay. The decoder includes the feature of using natural threshold FET devices in a transfer gate configuration to perform logical AND functions so as to minimize gate delays in decoding a carry condition for higher order stages. A selective upcounting or down- counting function is also disclosed.
摘要:
Eine erste Variante eines dynamischen Synchron-Binärzählers mit identischem Aufbau der Stufen, welcher in der üblichen Zweiphasen-Verhältnisschaltungstechnik mit nichtüberlappenden Taktsignalen angesteuert wird, besteht aus folgender signalflußmäßigen Serienschaltung: erster Inverter (11) - Komplexgatter (KG) - erster Transfertransistor (T1) - zweiter Inverter (12) - dritter Inverter (13). Das Komplexgatter (KG) besteht aus zwei NOR-verknüpften UND-Verknüpfungen (U1,U2). Der Ausgang des zweiten Inverters (12) ist der Vorwärtszähl-Ausgang (VA) und der des dritten Inverters (13) der Rückwärtszähl-Ausgang (RA). Der Vorwärtszähl-Ausgang (VA) liegt über den vom zweiten Taktsignal (F2) gesteuerten dritten Transfertransistor (T3) am ersten Eingang der UND-Verknüpfung (U1), deren zweiter Eingang mit dem Ausgang des ersten Inverters (11) verbunden ist. Der Rückwärtszähl-Ausgang (RA) liegt über den vom zweiten Taktsignal (F2) gesteuerten zweiten Transfertransistor (T2) am ersten Eingang der UND-Verknüpfung (U2), deren erster Eingang über einen vom Taktsignal (F2) gesteuerten fünften Transfertransistor (T5) mit dem Ausgang eines NOR-Gatters (NG) verbunden ist. Der eine Eingang des NOR-Gatters (NG) liegt am Übertrageingang (UE) einer jeden Stufen. Dieser Eingang ist über den Übertrag-Transfertransistor (UT) mit dem Übertragausgang (UA) verbunden. Der Übertrageingang (UE) der niederstwertigen Stufe liegt am Schaltungsnullpunkt. Der zweite Eingang des NOR-Gatters (NG) liegt an der Stoppleitung (S). Der Übertragausgang (UA) liegt über einen vom Rückwärtszähl-Ausgang (RA) gesteuerten vierten Transfertransistor (T4) an der konstanten Spannung (U). Bei einer zweiten Variante entfällt das Komplexgatter (KG), so daß der Ausgang des ersten Inverters (11) über den ersten Transfertransistor (T1') direkt mit dem Eingang des zweiten Inverters (12') verbunden ist. Ferner steuert der Ausgang des NOR-Gatters (NG') das Gate des zweiten Transfertransistors (T2'). Der erste Eingang des NOR-Gatters (NG') wird mit dem Taktsignal (F1') gespeist, der zweite Eingang liegt am Übertrageingang (UE). Die ausgang-abgewandten Enden der Strompfade der Transfertransistoren (T2', T3') führen jeweils zum Eingang des ersten Inverters (11').
摘要:
A regenerative frequency divider comprising an in-phase mixer circuit and a phase-shifted mixer circuit. At least one switching device of the in-phase mixer circuit is of a smaller scale than a corresponding switching device of the transconductance component of the in-phase mixer circuit. In some examples, at least one switching device within an input switching stage of the regenerative frequency divider forming part of the phase-shifted mixer circuit is of a smaller scale than a respective corresponding switching device within the input switching stage forming part of the in-phase mixer circuit. In some further examples, all switching devices within the phase-shifted mixer circuit are of a small scale than respective corresponding switching devices within the in-phase mixer circuit.
摘要:
A regenerative frequency divider comprising an in-phase mixer circuit and a phase-shifted mixer circuit. At least one switching device of the in-phase mixer circuit is of a smaller scale than a corresponding switching device of the transconductance component of the in-phase mixer circuit. In some examples, at least one switching device within an input switching stage of the regenerative frequency divider forming part of the phase-shifted mixer circuit is of a smaller scale than a respective corresponding switching device within the input switching stage forming part of the in-phase mixer circuit. In some further examples, all switching devices within the phase-shifted mixer circuit are of a small scale than respective corresponding switching devices within the in-phase mixer circuit.