High voltage level shifting IC with under-ground voltage swing withstanding capability
First Claim
1. A device operable to transfer an input signal between differently referenced circuits, comprising:
- an input circuit referenced to a first voltage reference and operable to provide the input signal;
a receiving device coupled to receive the input signal from the input circuit;
a biasing circuit coupled to the receiving device to provide a biasing voltage reference for the receiving device;
a first level shifter coupled to the input circuit and the receiving device for translating the input signal so it is referenced to the bias voltage;
an output circuit referenced to a second voltage reference; and
a second level shifter coupled to receive the translated input signal and to provide the translated input signal to the output circuit, whereby an output signal is provided which is related to the input signal and referenced to the second voltage reference.
2 Assignments
0 Petitions
Accused Products
Abstract
A level shifting circuit provides a reference bias voltage to permit signal transfer between two circuits with different common voltage reference levels. The bias voltage is less than a common voltage reference level for either of the two connected circuits. By providing the bias voltage, the range of variation for the common voltage reference levels between the two circuits is increased when the reference voltages float with respect to each other. The level shifting circuits permit signals to be transferred from a low voltage to a high voltage circuit with increased reliability and noise immunity, and vice versa. The level shifting circuit is particularly useful for driving a half bridge switch configuration, and transmitting a floating current sense signal.
-
Citations
23 Claims
-
1. A device operable to transfer an input signal between differently referenced circuits, comprising:
-
an input circuit referenced to a first voltage reference and operable to provide the input signal;
a receiving device coupled to receive the input signal from the input circuit;
a biasing circuit coupled to the receiving device to provide a biasing voltage reference for the receiving device;
a first level shifter coupled to the input circuit and the receiving device for translating the input signal so it is referenced to the bias voltage;
an output circuit referenced to a second voltage reference; and
a second level shifter coupled to receive the translated input signal and to provide the translated input signal to the output circuit, whereby an output signal is provided which is related to the input signal and referenced to the second voltage reference. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A device operable to transfer input signals between differently referenced circuits, comprising:
-
an input circuit referenced to a first voltage reference and operable to provide at least one input signal;
respective receiving devices coupled to receive each input signal from the input circuit;
a biasing circuit coupled to the receiving devices to provide a biasing voltage reference for the receiving devices;
respective first level shifters coupled to the input circuit and the receiving devices for translating the input signals so they are referenced to the bias voltage;
one or more output circuits referenced to a respective voltage reference for each input signal; and
respective second level shifters coupled to receive the translated input signals and to provide the translated input signals to the respective output circuits, whereby output signals are provided which are related to the input signals and referenced to the respective second voltage references. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A method for transferring an input signal from an input circuit referenced to a first voltage reference to an output circuit referenced to a second voltage reference, the method comprising the steps of:
-
providing a receiving device biased to a voltage below the first voltage reference;
coupling the input circuit through a first level shifter to the receiving device so that the input signal becomes referenced to the bias voltage reference;
transferring the input signal from the receiving device through a second level shifter to the output circuit whereby the transferred signal is referenced to the second voltage reference level; and
outputting the signal from the output circuit. - View Dependent Claims (21, 22, 23)
-
Specification