A method of performing coarse calibration of a voltage-mode (VM) driver having a plurality of driver slices connected in parallel includes setting a control code applied to activated driver slices of the plurality of driver slices to a maximum value to minimize an output resistance of the activated driver slices, activating one driver slice of the plurality of driver slices by applying the control code to the one driver slice, while disabling other driver slices of the plurality of driver slices, measuring an output resistance of the VM driver, determining whether the output resistance of the VM driver is greater than a desired resistance, and in response to determining that the output resistance of the VM driver is greater than a desired resistance activating one more driver slice of the plurality of driver slices.

The present invention relates to a novel and inventive compound device structure, enabling a charge-based approach that takes advantage of sub-threshold operation, for designing analog CMOS circuits. In particular, the present invention relates to a solid state device based on a complementary pair of n-type and p-type current field-effect transistors, each of which has two control ports, namely a low impedance port and gate control port, while a conventional solid state device has one control port, namely gate control port. This novel solid state device provides various improvement over the conventional devices.

An output buffer circuit includes an output node, a P-type transistor, an N-type transistor, and a first variable resistor circuit provided in a signal path between a drain of one of the P-type transistor and the N-type transistor and the output node.

One aspect disclosed features an apparatus comprising: an input buffer configured to receive an input voltage pulse as an input, and to output, responsive to a leading edge of the input voltage pulse, a logic high voltage pulse at a first output of the input buffer and a logic low voltage pulse at a second output of the input buffer; an array of L active pull-up devices electrically coupled between a positive supply rail and an output node, each active pull-up device driven by the logic high voltage pulse as modulated by a corresponding bit of a series of N first L-bit binary words; and an array of L active pull-down devices electrically coupled between a negative supply rail and the output node, each active pull-down device driven by the logic low voltage pulse as modulated by a corresponding bit of a series of M second L-bit binary words.

A power down signal generator generates a power down signal. The power down signal generator includes a detection transistor, a resistor coupled in series with the detection transistor, and a compensation transistor coupled in parallel to the resistor. The detection transistor receives a first supply voltage in a first voltage domain and a current. A control voltage is generated across the resistor based on a first part of the current. The compensation transistor receives a bias voltage derived from a second supply voltage in a second voltage domain and sinks, based on the bias voltage, a second part of the current to maintain the control voltage within a predefined range. The generation of the power down signal is controlled based on the first supply voltage and the control voltage.

An integrated circuit device includes: an integrated circuit module; a first field-effect transistor coupled between the integrated circuit module and a first reference voltage, and controlled by a first control signal; and a second field-effect transistor coupled between the integrated circuit module and the first reference voltage; wherein the second field-effect transistor is a complementary field-effect transistor of the first field-effect transistor, and the first field-effect transistor and the second field-effect transistor are configured to generate a second reference voltage for the integrated circuit module according to the first control signal.

A voltage control device includes a charge pump, a driving circuit, and a control circuit. The charge pump provides a first voltage. The driving circuit is coupled to the charge pump, and receives the first voltage and a reference voltage. The driving circuit outputs a driving signal according to an input signal, the first voltage and the reference voltage. The control circuit is coupled to the charge pump and the driving circuit. Before the first voltage reaches a threshold level, the control circuit adjusts the reference voltage to increase the voltage gap between the first voltage and the reference voltage.

Devices and methods for finite impulse response (FIR) feed forward equalization (FFE) at a transmitter are provided. A voltage-mode driver circuit has a main driver and an equalization driver. The main driver drives the digital output signal based on a received digital input signal. The equalization function of the equalization driver is enabled or disabled for a short duration of time to provide at least one of FIR equalization and pre-emphasis to the digital output signal. Pre-emphasis is effected by enabling a low-resistance path of the equalization driver based on the digital input signal such that, when the low-resistance path is enabled, it reduces the transmission resistance for a short period of time.

A bias current circuit which includes: a main unit including first PMOS and NMOS transistors constituting a first current path, and second PMOS and NMOS transistors constituting a second current path together with a first resistor; an output unit; and a supply voltage adapting unit including a third MOS transistor, a pull-up current source and a pull-down current source. The third MOS transistor is connected between a first node to which gates of the first and second PMOS transistors are connected and a second node to which drains of the second NMOS and PMOS transistors are connected. The pull-up current source is mirrored to the first PMOS transistor and configured to provide a current equal to a current provided by the pull-down current source. The bias current circuit has an operating voltage range encompassing low-voltage band such that it is operable at high and low voltages.

A level shifter includes: an input circuit receiving an input signal swinging between a reference voltage and a first power supply voltage having a level higher than a level of the reference voltage; an output circuit outputting an output signal swinging between a second power supply voltage having a level higher than the level of the first power supply voltage and a third power supply voltage having a level higher than the level of the second power supply voltage; and a tolerant circuit connected between the input circuit and the output circuit, and configured to limit an output voltage of the input circuit to a range between the reference voltage and the second power supply voltage.