摘要:
A PLL circuit includes phase comparator (103) having a first input terminal to which a reference clock is applied; charge pump (104) generating a voltage conforming to a phase difference output from the phase comparator; loop filter (105); VCO (106); frequency dividing circuit (107), to which an output clock of the VCO is input, performing frequency-division by P; A counter (109) dividing the output of the frequency dividing circuit by a second value A; circuits (121,122) generating two signals, which have a phase difference equivalent to one period of the P-frequency-divided output of the frequency dividing circuit, whenever frequency-division by A is performed by the A counter; and interpolator (123), to which the two generated signals are input, producing an output signal of a phase obtained by interpolating the phase difference between the two signals in accordance with an interior division ratio set by a control signal.
摘要:
Zur Programmierung der Verzögerungszeit eines Signalpfads (1, 2), insbesondere in DRAMs, umfaßt die Schaltungsanordnung zwei eingangsseitig parallel ansteuerbare Signalstrecken (3, 4) mit unterschiedlicher Verzögerungszeit, die über einen Multiplexer auf den Ausgangsanschluß (2) schaltbar sind. Eine Auswahlschaltung (5) umfaßt zwei zwischen die Versorgungsspannung (VDD, VSS) geschaltete Signalstrecken mit zwei in Reihe geschalteten komplementären Transistoren (511, 512; 521, 522) sowie sourceseitigen programmierbaren Elementen. Die Transistoren sind von komplementären Steuersignalen (HSPEED, bHSPEED) ansteuerbar. Dadurch wird eine flexible Programmierung der Verzögerungszeit bei geringem Schaltungsaufwand ermöglicht.
摘要:
A CMOS gate is provided which has a programmable driving power characteristic so that its propagation delay time can be varied by digital select control signals (S1-Sm). The CMOS gate includes a programmable inverter section (12) formed of a plurality of inverters (12a-12m), a switching logic control section (14), and a static inverter (16). The switching logic control signal section is responsive to the digital select control signals for selectively programming a certain number of the plurality of inverters to be enabled. In this manner, a certain number of the plurality of inverters will be wired in parallel with the static inverter in order to produce the desired amount of propagation delay time.
摘要:
Le procédé fournit un signal de sortie (S K ) présentant un retard variable par rapport à un signal d'entrée (e₀). Pour permettre un réglage précis en fonction d'une consigne de retard (CN) sur plusieurs gammes, le procédé consiste à produire une succession de signaux retardés (e₁, e₂, ..., e n ) par rapport au signal d'entrée (e₀) , le retard entre un signal retardé (e₂) et le signal précédent (e₁) ayant une valeur prédéterminée, à sélectionner l'un desdits signaux retardés (e₂) et le signal précédent (e₁) et à effectuer une superposition avec pondération et effet intégral desdits signaux sélectionnés (e₁, e₂), ladite sélection et ladite pondération étant déterminées en fonction de ladite consigne de retard (CN). Réalisations en technologie ECL et CMOS. Application notamment aux circuits verrouillés en phase.
摘要:
A CMOS digital-controlled delay gate (10) is provided in which the propagation delay time can be precisely controlled by digital select control signals (Sp1-Snm). The delay gate (10) includes an inverter circuit section (12) formed of a plurality of CMOS inverters (12a-12n) each inverter having a P-channel transistor and an N-channel transistor and a control logic section (14,16) which is responsive to the digital select control signals (Sp1-Snm) for changing the ratio of the total P-channel transistor size to the total N-channel transistor size in the enabled transistors. The input threshold voltage of the inverter circuit section (12) is selectively changeable so as to produce a controllable propagation delay.
摘要:
A variable delay circuit includes a first power source line (140, 12, 25, 42, 60) for supplying a first power source voltage (V DD ), a second power source line (143, 13, 26, 43, 61) for supplying a second power source voltage (V SS ) which is smaller than the first power source voltage, an input terminal (145, 9, 22, 37, 57) for receiving an input signal (IN), a selection terminal (148, 10, 23, 38-40, 58) for receiving a selection signal (S, S₁-S₃), an output terminal (141, 11, 24, 41, 59) for outputting an output signal (OUT) which is delayed relative to the input signal, a pull-up circuit (142) coupled between the first power source line and the output terminal for carrying out a pull-up operation based on the input signal which is received via the input terminal, and a pull-down circuit (144) coupled between the output terminal and the second power source line for carrying out a pull-down operation based on the input signal which is received via the input terminal. The pull-up or pull-down circuit has a delay time which is variable in response to the selection signal which is received via the selection terminal.
摘要:
A constant time delay circuit which is insensitive to variations in temperature and has no D.C. power dissipation includes a temperature-insensitive reference current source (12) for dynamically charging and discharging a capacitive load (M5), a polysilicon resistor (16), and at least one time delay control circuit (14) to produce a constant time delay. In an alternate embodiment, there is provided a temperature self-compensated programmable delay circuit which includes electrically programmable resistor means (30) for adjusting the total resistance in a temperature-insensitive reference current source (12b). As a result, the amount of the reference current is controlled so as to obtain a desired delay time.
摘要:
Circuit de temporisation (10) comprenant un premier circuit onduleur (10) couplé entre une première source de tension (TCC) et un potentiel de référence par une pluralité de transistors (Q5-Q19) connectés en parallèle. Chacun des transistors (Q5-Q19) a une porte de commande (DY1- DY15) pouvant être sélectionnée pour mettre la résistance du transistor en circuit avec le circuit onduleur (20), pour commander le rythme de charge d'une capacité répartie. Un circuit de sortie (40) couplé au premier circuit onduleur (20) fournit la capacité répartie ainsi qu'une sortie tamponnée inversée (DBUF). Le circuit de sortie comprend également une sortie (DOUT) pouvant être connectée à un autre circuit identique au circuit de temporisation (10), pour former un circuit de temporisation en cascade pouvant recevoir un signal de remise à zéro afin de remettre à zéro le circuit de temporisation en cascade.
摘要:
A feedback loop circuit includes a phase detector and delay circuits. The phase detector generates an output signal based on a delayed periodic signal. The delay circuits are coupled in a delay chain that delays the delayed periodic signal. Each of the delay circuits comprises variable and fixed delay blocks that are coupled to form at least two delay paths for an input signal through the delay circuit to generate a delayed output signal. Delays of the variable delay blocks in the delay circuits vary based on the output signal of the phase detector. Each of the delay circuits reroutes the input signal through a different one of the delay paths to generate the delayed output signal based on the output signal of the phase detector during operation of the feedback loop circuit. Each of the variable and fixed delay blocks inverts a received signal to generate an inverted signal.