Nan Ya Technology Corporation

Chang-Ting Wu

Hao-Huan Hsu

An off-chip driver (OCD), a pull-up driver of the OCD and the pull-down driver of the OCD are provided. The pull-up driver includes a main current source circuit and a main base circuit. The main current source circuit is connected between a connecting pad and a high reference voltage. The main current source circuit provides a main current value in response to a main control signal. The matching resistance value is associated with the main current value. The main base circuit is connected to the main current source circuit in parallel, and determines a base value of the matching resistance value.

Off-chip driver and driving circuit for providing matching resistance value

An off-chip driving device and a driving capability enhancement method thereof are provided. Detecting a rising edge and a falling edge of an input data signal. A first enhancement circuit is controlled to provide a first enhancement signal to an input/output pad according to the rising edge and the falling edge of the input data signal.

Off-chip driving device and driving capability enhancement method thereof

An off-chip driver (OCD), including a pull-up driver and a pull-down driver, is provided. The pull-up driver and the pull-down driver are coupled to an output pad. One of the pull-up driver and the pull-down driver includes a main driving circuit, an auxiliary driving circuit, a connection circuit, and a common impedance. The main driving circuit is used to perform an output driving operation on the output pad, and the auxiliary driving circuit is used to selectively perform the output driving operation on the output pad. A first terminal of the common impedance is coupled to a driving terminal of the main driving circuit and a driving terminal of the auxiliary driving circuit through the connection circuit. A second terminal of the common impedance is coupled to the output pad.

Off-chip driver

An electrical over stress protection device is provided. A detection circuit detects an input voltage from a pad, provides a first discharge path when the input voltage is higher than a preset voltage, and provides a turn-on voltage to a discharge protection circuit to control the discharge protection circuit to provide at least one second discharge path.

Electrical over stress protection device

A clock detecting circuit is provided. The clock detecting circuit includes a first clock converting circuit, a second clock converting circuit and a frequency comparator. The first clock converting circuit converts an internal clock to a first clock. The second clock converting circuit converts an external clock to a second clock. The frequency comparator generates a first edge clock in response the first clock and generates a second edge clock in response the second clock. The frequency comparator generates a first sensing voltage in response to a plurality of positive pulses of the first edge clock and generate a second sensing voltage in response to a plurality of positive pulses of the second edge clock. The frequency comparator compares the first sensing voltage and the second sensing voltage to provide a frequency comparing result between the external clock and the internal clock.

Clock detecting circuit

The off-chip driving (OCD) device includes a signal transition detector, a front-end driver, a first main driver, a second main driver, a first resistance provider and a second resistance provider. The signal transition detector is used to detect a transition status of an input signal to generate decision information. The front-end driver generates control signals according to the decision information, and generates driving signals according to the input signal. The first main driver and the second main driver generate an output signal to a pad according to the driving signals. The first resistance provider adjusts a first resistance between the first main driver and the pad according to a first control signal. The second resistance provider adjusts a second resistance between the second main driver and the pad according to a second control signal.

Off-chip driving device

An off chip driver circuit includes a first power rail, a second power rail, an input/output pad, a pull-up circuit, a pull-down circuit. The pull-up circuit is configured to selectively activate at least one of charging paths between the first power rail and the input/output pad. The pull-up circuit includes a first resistor and PMOS transistors arranged on the charging paths, and the first resistor is coupled between the first power rail and the PMOS transistors. The pull-down circuit is configured to selectively activate at least one of discharging paths between the second power rail and the input/output pad. The pull-down circuit includes a second resistor and NMOS transistors arranged on the discharging paths, and the second resistor is coupled between the second power rail and the NMOS transistors.

Off chip driver circuit, off chip driver system, and method for manufacturing an off chip driver circuit

The interface circuit includes a first transistor, a second transistor, a first switch, a first logic circuit and a second logic circuit. The first transistor is controlled by a enable signal. The second transistor is controlled by a first control signal. The first switch is coupled between a second end of the first transistor and the output end of the interface circuit, wherein the first switch is controlled by a second control signal. The first logic circuit generates the first control signal according to the enable signal and at least one indication signal. The second logic circuit generates the second control signal according to the first control signal and the enable signal.

Interface circuit

An off chip driver circuit includes a pull-up circuit and a pull-down circuit. The pull-up circuit includes several first transistors and a first resistance circuit coupled between the first transistors and a input/output pad. The first transistors generate a first voltage to the first resistance circuit. The first resistance circuit transmits, in response to a first control signal, the first voltage to the input/output pad and to have a variable resistance according to the first control signal. The pull-down circuit includes several second transistors and a second resistance circuit coupled between the second transistors and the input/output pad. The second transistors generate a second voltage to the second resistance circuit. The second resistance circuit transmits, in response to a second control signal, the second voltage to the input/output pad and to have a variable resistance according to the second control signal.

Off chip driver circuit, off chip driver system, and method for operating an off chip driver circuit

This invention provides a resistance-adjustable means using at a pull-up driver and/or a pull-down driver of an OCD circuit. When the resistance-adjustable means is applicable to the pull-up driver, the resistance-adjustable means includes a triode-mode PMOS coupled to a circuit of the pull-up driver and at least one of one or more adjustable resistors and/or a fixed resistor, which are connected in series and coupled to the triode-mode PMOS, and the at least one of the adjustable resistors or the fixed resistor is coupled to an IO (input/output) pad. When the resistance-adjustable means is applicable to the pull-down driver, a triode-mode NMOS is used to replace the triode-mode PMOS for the resistance-adjustable means.

Resistance-adjustable means using at a pull-up or pull-down driver of an OCD circuit

An off chip driving system includes a decision circuit, multiple first and second adjustable-enhancement circuits, and multiple first and second drivers. The decision circuit outputs a first and a second decision signal according to a clock and an input data. Each first adjustable-enhancement circuit generates one of first control signals in response to the first and the second decision signal and one of first optional signals. Each second adjustable-enhancement circuit generates one of second control signals in response to the first and the second decision signal and one of second optional signals. Each first driver is coupled to the corresponding first adjustable-enhancement circuit and configured to be enabled in response to the corresponding first control signal. Each second driver is coupled to the corresponding second adjustable-enhancement circuit and configured to be enabled in response to the corresponding second control signal.

Off chip driving system and signal compensation method

An off chip driving circuit includes a decision circuit, a first compensation circuit, a second compensation circuit, a pull-up circuit and a pull-down circuit. The decision circuit is configured to output a first decision signal and a second decision signal according to a clock and an input data. The first compensation circuit is coupled to the decision circuit and configured to generate a first control signal in response to the first decision signal and the second decision signal. The second compensation circuit is coupled to the decision circuit and configured to generate a second control signal in response to the first decision signal and the second decision signal. The pull-up circuit is configured to be enabled in response to the first control signal. The pull-down circuit is configured to be enabled in response to the second control signal.

Off chip driving circuit and signal compensation method

An OCD circuit includes a pull-up circuit, a pull-down circuit, a first and a second compensation circuit. The pull-up circuit is enabled in response to an input data. The pull-down circuit is enabled in response to the input data. The first compensation circuit is coupled to the pull-up circuit and configured to induce a first compensation signal to the pull-up circuit in response to a first decision signal. The second compensation circuit is coupled to the pull-down circuit and configured to induce a second compensation signal to the pull-down circuit in response to a second decision signal. The first decision signal and the second decision signal are generated in response to the input data.

Off chip driver circuit, off chip driver compensation system and signal compensation method

The present disclosure provides an off-chip driver (OCD) and an associated DRAM. The OCD operates in a power domain. The power domain works under a minimum system voltage and a maximum system voltage. The OCD is configured for providing a drive current to an output pad. The OCD includes a pull-push circuit. The pull-push circuit is coupled to the output pad. The pull-push circuit includes a current source circuit. The current source circuit includes a VCCS. The VCCS is configured to provide, in response to an operation voltage, an impedance with respect to the output pad, wherein the operation voltage ranges between the minimum system voltage and the maximum system voltage.

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Hsinchu County, Taiwan

Chang-Ting Wu